opinion: Justice O’Connor
  delivered the opinion of the Court.
  We decide today whether, at the end of a strike, an employer is required by the Railway Labor Act (RLA or Act), 44 Stat. 577, as amended, 45 U. S. C. § 151 et seq., to displace employees who worked during the strike in order to reinstate striking employees with greater seniority.
  HH
  In March 1984, Trans World Airlines, Inc. (TWA), and the Independent Federation of Flight Attendants (IFFA or Union) began negotiations pursuant to §6 of the RLA, 45 U. S. C. § 156, on a new collective bargaining agreement to replace their prior agreement due to expire on July 31, 1984. The existing collective bargaining agreement created a complex system of bidding the general effect of which was to insure that those flight attendants with the greatest seniority would have the best opportunity to obtain their preferred job assignments, flight schedules, and bases of operation as vacancies appeared, and to insure that senior flight attendants would be least affected by the periodic furloughs endemic to the airline industry. Thus, for example, should a job vacancy appear at the highly desirable Los Angeles or San Francisco bases of operation or “domiciles,” the most senior qualified flight attendant who bid on such a vacancy would be entitled to it. Conversely, should a reduction in force eliminate a position in the Los Angeles domicile, the furloughed flight attendant could opt to displace the most junior attendant of equal rank in the entire system or the most junior attendant of lower rank either at the same domicile or in the entire system. 1981-1984 TWA/IFFA Collective Bargaining Agreement, Arts. 12-13, 18-A, 18-B, reprinted in App. 31-62.
  For two years TWA and the Union unsuccessfully bargained over wages and working conditions not including the seniority bidding system. They pursued all the required dispute resolution mechanisms of the RLA, including direct negotiation, 45 U. S. C. § 152 Second, mediation, 45 U. S. C. § 155 First, and the final 30-day “cooling off” period. Ibid. By early 1986 a strike seemed imminent, and on March 7, 1986, the Union went out on strike.
  TWA informed its flight attendants before and during the strike that it would continue operations by hiring permanent replacements for striking flight attendants, by continuing to employ any flight attendant who chose not to strike, and by rehiring any striker who abandoned the strike and made an unconditional offer to return to any available vacancies. TWA also informed its flight attendants that any vacancies created as a result of the strike would be filled by application of the seniority bidding system to all working flight attendants and that such job and domicile assignments would remain effective after the strike ended. App. 120-122, 132-134, 137-139. Thus, at the conclusion of the strike, senior full-term strikers would not be permitted to displace permanent replacements or junior nonstriking flight attendants and could be left without an opportunity to return to work. TWA’s promise not to displace working flight attendants after the strike created two incentives specifically linked to the seniority bidding system: it gave senior flight attendants an incentive to remain at, or return to, work in order to retain their prior jobs and domicile assignments; it gave junior flight attendants an incentive to remain at, or return to, work in order to obtain job and domicile assignments that were previously occupied by more senior, striking flight attendants.
  As promised, TWA continued its operations during the 72-day strike by utilizing approximately 1,280 flight attendants who either did not strike or returned to work before the end of the strike and by hiring and fully training approximately 2,350 new flight attendants, some 1,220 of whom were hired during the first few days of the strike. On May 17, 1986, the Union made an unconditional offer to TWA on behalf of the approximately 5,000 flight attendants who had remained on strike to return to work. TWA accepted the offer but refused the Union’s May 27th demand that TWA displace those prestrike employees who were working as of May 17th (“crossover” employees). Accordingly, TWA initially recalled only the 197 most senior full-term strikers to fill available job and domicile vacancies. By the terms of a poststrike arbitral agreement, these strikers and all subsequently reinstated full-term strikers returned to work as vacancies arose and with precisely the seniority they would have had if no strike had occurred. In May 1988, more than 1,100 full-term strikers had been reinstated with full seniority.
  In an effort to reinstate all the full-term strikers by displacing the newly hired flight attendants and less senior crossover employees, the Union proceeded on two fronts. First, it brought an injunction action alleging that the full-term strikers were not “economic strikers” but “unfair labor practice strikers” entitled to reinstatement by application of principles this Court has developed in interpreting the National Labor Relations Act (NLRA). 29 U. S. C. § 151 et seq. See Mastro Plastics Corp. v. NLRB, 350 U. S. 270 (1956). The District Court ultimately ruled against the Union on this claim. Independent Federation of Flight Attendants v. Trans World Airlines, Inc., 682 F. Supp. 1003 (WD Mo. 1988), appeal pending, No. 88-1984M (CA8). At the same time, the Union filed the instant action contending that, even assuming the strike was economic, the full-term strikers were entitled to reinstatement either under the terms of the prestrike collective bargaining agreement or under the RLA itself. On cross motions for partial summary judgment, the District Court held that the full-term strikers were not entitled to displace either the junior crossovers or the 1,220 new hires employed by TWA immediately after the strike commenced. (The motions did not require the District Court to rule on the status of the remaining new hires.) The District Court also held that 463 new hires not fully trained by the end of the strike could be displaced by full-term strikers. Independent Federation of Flight Attendants v. Trans World Airlines, Inc., 643 F. Supp. 470 (WD Mo. 1986).
  Meanwhile, TWA sought a declaratory judgment that the union security clause of the prestrike collective bargaining agreement containing provisions for the checkoff of union dues and a requirement that new hires join the Union did not survive the self-help period after the parties had bargained to impasse. On cross motions for summary judgment, the same District Court ruled that, because the union security clause was not part of the prestrike negotiations, it had survived the strike. Trans World Airlines, Inc. v. Independent Federation of Flight Attendants, 640 F. Supp. 1108 (WD Mo. 1986).
  Appeals were taken from both judgments. The Court of Appeals affirmed the District Court’s ruling that the union security clause had survived the period of self-help. Trans World Airlines, Inc. v. Independent Federation of Flight Attendants, 809 F. 2d 483 (CA8 1987). In a separate opinion, the same panel also affirmed the District Court’s ruling that full-term strikers could not displace the 1,220 fully trained new hires but could displace the 463 untrained new hires. Independent Federation of Flight Attendants v. Trans World Airlines, Inc., 819 F. 2d 839 (CA8 1987). The Court of Appeals, however, reversed the District Court’s ruling that more senior full-term strikers could not displace junior crossovers. In so holding, the court relied primarily on its reading of the union security clause of the prestrike collective bargaining agreement and, secondarily, on judicial interpretations of the NLRA. Id., at 843-845.
  We granted petitions for writs of certiorari in both cases. Trans World Airlines, Inc. v. Flight Attendants, 482 U. S. 913 (1987) (TWA I); Flight Attendants v. Trans World Airlines, Inc., 485 U. S. 958 (1988) (TWA II) (certiorari granted only to consider displacement of crossovers). Last Term, we affirmed by an equally divided Court the judgment of the Court of Appeals in TWA I that the union security clause survived the strike. 485 U. S. 175 (1988). Today, we reverse the Court of Appeals in TWA II and hold that an employer is not required by the RLA to lay off junior crossovers in order to reinstate more senior full-term strikers at the conclusion of a strike.
  II
  We have observed in the past that carefully drawn analogies from the federal common labor law developed under the NLRA may be helpful in deciding cases under the RLA. Trainmen v. Jacksonville Terminal Co., 394 U. S. 369, 377 (1969). Thus, as in this case, those lower courts that have examined the reinstatement rights of strikers under the RLA have turned to NLRA precedents for guidance. E. g., Air Line Pilots Assn. International v. United Air Lines, Inc., 614 F. Supp. 1020, 1041, 1045-1046 (ND Ill. 1985), aff’d in part and rev’d in part on other grounds, 802 F. 2d 886 (CA7 1986), cert. denied, 480 U. S. 946 (1987); National Airlines, Inc. v. International Assn. of Machinists & Aerospace Workers, 416 F. 2d 998, 1004-1006 (CA5 1969).
  We first considered the reinstatement rights of strikers under the NLRA in NLRB v. Mackay Radio & Telegraph Co., 304 U. S. 333 (1938). In Mackay Radio, radio and telegraph operators working in the San Francisco offices of a national telecommunications firm went on strike. In order to continue operations, the employer brought employees from its other offices to fill the strikers’ places. At the conclusion of the strike, the striking operators sought to displace their replacements in order to return to work. We held that it was not an unfair labor practice under § 8 of the NLRA for the employer to have replaced the striking employees with others “in an effort to carry on the business,” or to have refused to discharge the replacements in order to make room for the strikers at the conclusion of the strike. Id., at 345-346. As we there observed, “[t]he assurance by [the employer] to those who accepted employment during the strike that if they so desired their places might be permanent was not an unfair labor practice nor was it such to reinstate only so many of the strikers as there were vacant places to be filled.” Id., at 346. On various occasions we have reaffirmed the holding of Mackay Radio. See NLRB v. Erie Resistor Corp., 373 U. S. 221, 232 (1963) (“We have no intention of questioning the continuing vitality of the Mackay rule . . .”); NLRB v. Fleetwood Trailer Co., 389 U. S. 375, 379 (1967) (Employers have “ ‘legitimate and substantial business justifications’ for refusing to reinstate employees who engaged in an economic strike . . . when the jobs claimed by the strikers are occupied by workers hired as permanent replacements during the strike in order to continue operations”); Belknap, Inc. v. Hale, 463 U. S. 491, 604, n. 8 (1983) (“The refusal to fire permanent replacements because of commitments made to them in the course of an economic strike satisfies the requirement. . . that the employer have a ‘legitimate and substantial justification’ for its refusal to reinstate strikers”).
  TWA asks us to apply this line of cases decided under the NLRA to determine the status under the RLA of those prestrike flight attendants who were working at the conclusion of the strike. TWA argues that it would be completely anomalous to hold that full-term strikers may displace junior crossovers when, as the Union has conceded, they may not displace newly hired permanent replacements under either statute. The Union, by contrast, argues that the rule of Mackay Radio is inapplicable to junior crossovers because of differences between the RLA and the NLRA and because, even under the NLRA, junior crossovers would be treated differently from newly hired permanent replacements.
  The Union relies on Erie Resistor, supra, to distinguish junior crossovers from new hires under the NLRA. In Erie Resistor we struck down an employer’s award of 20 years’ superseniority to new hires and crossovers as an unfair labor practice within the meaning of § 8(a)(1) and § 8(a)(3) of the NLRA. 29 U. S. C. §§ 158(a)(1), 158(a)(3). We observed:
  “. . . Super-seniority affects the tenure of all strikers whereas permanent replacement, proper under Mackay, affects only those who are, in actuality, replaced. It is one thing to say that a striker is subject to loss of his job at the strike’s end but quite another to hold that in addition to the threat of replacement, all strikers will at best return to their jobs with seniority inferior to that of the replacements and of those who left the strike.
  “. . . Unlike the replacement granted in Mackay which ceases to be an issue once the strike is over, the [superseniority] plan here creates a cleavage in the plant continuing long after the strike is ended. Employees are henceforth divided into two camps: those who stayed with the union and those who returned before the end of the strike and thereby gained extra seniority. This breach is reemphasized with each subsequent layoff and stands as an ever-present reminder of the dangers connected with striking and with union activities in general.” 373 U. S., at 230-231.
  The Union does not and cannot contend that reinstated full-term strikers have less seniority relative to new hires and junior crossovers than they would have had if they had not remained on strike. It is clear that reinstated full-term strikers lost no seniority either in absolute or relative terms. Thus, unlike the situation in Erie Resistor, any future reductions in force at TWA will permit reinstated full-term strikers to displace junior flight attendants exactly as would have been the case in the absence of any strike. Similarly, should any vacancies develop in desirable job assignments or domiciles, reinstated full-term strikers who have bid on those vacancies will maintain their priority over junior flight attendants, whether they are new hires, crossovers, or full-term strikers. In the same vein, periodic bids on job scheduling will find senior reinstated full-term strikers maintaining their priority over all their junior colleagues. In short, once reinstated, the seniority of full-term strikers is in no way affected by their decision to strike.
  Nevertheless, IFFA argues that TWA’s refusal to displace junior crossovers will create a “cleavage” between junior crossovers and reinstated full-term strikers at TWA “long after the strike is ended.” Id., at 231. This is the case because desirable job assignments and domiciles that would have been occupied by the most senior flight attendants had there been no strike will continue to be held by those who did not see the strike through to its conclusion. For example, the senior full-term striker who worked in the Los Angeles domicile before the strike may have been replaced by a junior crossover. As poststrike vacancies develop in TWA’s work force, permitting reinstatement of full-term strikers, they are not likely to occur in the most desirable domiciles. Thus, it is unlikely that the senior full-term striker would be reinstated back to her preferred domicile. Resentful rifts among employees will also persist after the strike, the Union argues, because TWA’s prestrike assurance of nondisplacement to junior crossovers, unlike the same assurance to new hires, “set up- a competition among those individuals who participated in the original decision to strike, and thereby undermined the group’s ability to take the collective action that it is the very purpose of the [RLA] to protect.” Brief for Respondent 36-37.
  We reject this effort to expand Erie Resistor. Both the RLA and the NLRA protect an employee’s right to choose not to strike. 45 U. S. C. § 152 Fourth; 29 U. S. C. § 157, and, thereby, protect employees’ rights to “the benefit of their individual decisions not to strike . . . .” Post, at 448, n. 4 (Brennan, J., dissenting). Accordingly, in virtually every strike situation there will be some employees who disagree with their union’s decision to strike and who cannot be required to abide by that decision. It is the inevitable effect of an employer’s use of the economic weapons available during a period of self-help that these differences will be exacerbated and that poststrike resentments may be created. Thus, for example, the employer’s right to hire permanent replacements in order to continue operations will inevitably also have the effect of dividing striking employees between those who, fearful of permanently losing their jobs, return to work and those who remain stalwart in the strike. In such a situation, apart from the “pressure on the strikers as a group to abandon the strike,” to which the dissent refers, post, at 449 (Brennan, J., dissenting), a “competition” may arise among the striking employees to return to work in order to avoid being displaced by a permanent replacement. Similarly, employee awareness that an employer may decide to transfer working employees to necessary positions previously occupied by more senior striking employees will isolate employees fearful of losing those positions and employees coveting those positions from employees more committed to the strike. Conversely, a policy such as TWA employed here, in creating the incentive for individual strikers to return to work, also “puts pressure on the strikers as a group to abandon the strike,” ibid., in the same manner that the hiring of permanent replacements does.
  None of these scenarios, however, present the prospect of a continuing diminution of seniority upon reinstatement at the end of the strike that was central to our decision in Erie Resistor. All that has occurred is that the employer has filled vacancies created by striking employees. Some of these vacancies will be filled by newly hired employees, others by doubtless more experienced and therefore more needed employees who either refused to strike or abandoned the strike. The dissent’s observation that, “at the conclusion of the strike,” discrimination in the filling of “available positions” based on union activity is impermissible is beside the point. See post, at 450 (Brennan, J., dissenting). The positions occupied by newly hired replacements, employees who refused to strike, and employees who abandoned the strike are simply not “available positions” to be filled. As noted above, those positions that were available at the conclusion of the strike were filled “according to some principle, such as seniority, that is neutral. . . .” Ibid. (Brennan, J., dissenting). That the prospect of a reduction in available positions may divide employees and create incentives among them to remain at work or abandon a strike before its conclusion is a secondary effect fairly within the arsenal of economic weapons available to employers during a period of self-help.
  To distinguish crossovers from new hires in the manner IFFA proposes would have the effect of penalizing those who decided not to strike in order to benefit those who did. Because permanent replacements need not be discharged at the conclusion of a strike in which the union has been unsuccessful, a certain number of prestrike employees will find themselves without work. We see no reason why those employees who chose not to gamble on the success of the strike should suffer the consequences when the gamble proves unsuccessful. Requiring junior crossovers, who cannot themselves displace the newly hired permanent replacements, and “who rank lowest in seniority,” post, at 447 (Brennan, J., dissenting), to be displaced by more senior full-term strikers is precisely to visit the consequences of the lost gamble on those who refused to take the risk. While the employer and union in many circumstances may reach a back-to-work agreement that would displace crossovers and new hires or an employer may unilaterally decide to permit such displacement, nothing in the NLRA or the federal common law we have developed under that statute requires such a result. That such agreements are typically one mark of a successful strike is yet another indication that crossovers opted not to gamble; if the strike was successful the advantage gained by declining to strike disappears.
  J — I HH
  The Union argues, however, that whether or not the NLRA prohibits a crossover policy such as TWA’s, the statutory framework of the RLA forbids such a policy.
  Although we have observed that the NLRA may provide useful analogies for interpreting the RLA, we have also emphasized that the NLRA “cannot be imported wholesale into the railway labor arena. Even rough analogies must be drawn circumspectly with due regard for the many differences between the statutory schemes.” Trainmen v. Jacksonville Terminal, 394 U. S., at 383. Thus, in Trainmen itself we declined to examine the “panoply of detailed law developed” under the NLRA to determine what kind of secondary picketing in a railway dispute may be enjoined by state courts. Rather, we held that Congress had entirely withdrawn such injunctive power from the States: “[Pjarties who have unsuccessfully exhausted the Railway Labor Act’s procedures for resolution of a major dispute . . . [may] employ the full range of whatever peaceful economic power they can muster, so long as its use conflicts with no other obligation imposed by federal law.” Id., at 391-392. Similarly, two Terms ago in Burlington Northern R. Co. v. Maintenance of Way Employes, 481 U. S. 429 (1987), we declined to find in the RLA an implied limit on a union’s resort to secondary activity by analogy to the NLRA. These cases have read the RLA to provide greater avenues of self-help to parties that have exhausted the statute’s “virtually endless,” id., at 444, dispute resolution mechanisms than would be available under the NLRA. Nevertheless, they provide the backdrop for the Union’s contention that, in this case, we should understand provisions of the RLA to limit “the full range of whatever peaceful economic power [the parties] can muster,” Trainmen, supra, at 392, beyond the limitations even imposed by the NLRA. This we decline to do.
  The Union points to § 2 Fourth of the RLA as the source of this limitation on the use of the employer’s economic power. The section provides, in pertinent part:
  “No carrier, its officers or agents shall deny or in any way question the right of its employees to join, organize, or assist in organizing the labor organization of their choice, and it shall be unlawful for any carrier to interfere in any way with the organization of its employees, ... or to influence or coerce employees in an effort to induce them to join or remain or not to join or remain members of any labor organization . . . .” 45 U. S. C. § 152 Fourth.
  The Union argues that TWA’s crossover policy, which created an incentive for flight attendants either not to join or to abandon the strike, constituted influence or coercion in an effort to induce the flight attendants not to remain members of IFFA and was, therefore, impermissible under §2 Fourth.
  Section 2 Fourth was enacted as part of the 1934 amendments to the RLA. 48 Stat. 1185. From the time of our very first opportunity to interpret the 1934 amendments, we have viewed them as addressing primarily the precertification rights and freedoms of unorganized employees. In Virginian R. Co. v. Railway Employees, 300 U. S. 515 (1937), we observed that the employees’ freedom “to organize and to make choice of their representatives without the ‘coercive interference’ and ‘pressure’ of a company union . . . was continued and made more explicit by the amendment of 1934.” Id., at 543, citing § 2 Third, § 2 Fourth, and Texas & N. O. R. Co. v. Railway Clerks, 281 U. S. 548 (1930). In Switchmen v. National Mediation Bd., 320 U. S. 297 (1943), the Court divided over whether the federal courts have jurisdiction under § 2 Fourth to review a certification of union representatives for collective bargaining by the National Mediation Board acting under § 2 Ninth of the RLA as amended in 1934. Both the majority and the dissent agreed, however, that “[t]he 1934 Act was directed particularly at control over the initial step in collective bargaining — the determination of the employees’ representatives.” Id., at 317 (Reed, J., dissenting); see also id., at 302 (opinion of the Court); Machinists v. Street, 367 U. S. 740, 759 (1961).
  The explanation for the precertification focus of the 1934 amendments is clear. The RLA provides an exhaustively detailed procedural framework “to facilitate the voluntary settlement of major disputes.” Trainmen v. Jacksonville Terminal, supra, at 378. The effectiveness of these private dispute resolution procedures depends on the initial assurance that the employees’ putative representative is not subject to control by the employer and on the subsequent assurance that neither party will be able to enlist the courts to further its own partisan ends. See Chicago & N. W. R. Co. v. Transportation Union, 402 U. S. 570, 596-597 (1971) (Brennan, J., dissenting) (the duty to exhaust the dispute resolution procedures “does not contemplate that governmental power should, after failure of the parties to reach accord, be added to the scales in favor of either party and thus compel the other to agree upon the aided party’s terms. Rather, at that point, impasse was to free both parties to resort to self-help”); Burlington Northern, supra, at 451-452 (the availability of self-help measures rather than judicial remedies “may increase the effectiveness of the RLA in settling major disputes by creating an incentive for the parties to settle prior to exhaustion of the statutory procedures”). Thus, we have understood judicial intervention in RLA procedures to be limited to those cases where “but for the general jurisdiction of the federal courts there would be no remedy to enforce the statutory commands which Congress had written into the Railway Labor Act.” Switchmen, supra, at 300; Chicago & N. W. R. Co., supra, at 595 (Brennan, J., dissenting) (“The underlying cohesiveness of the decisions [permitting judicial interference] lies in the fact that in each instance the scheme of the Railway Labor Act could not begin to work without judicial involvement”).
  Here, TWA and the Union followed without interference the scheme of the RLA to an unsuccessful conclusion and then turned to self-help. We have more than once observed that, at this final stage of a labor dispute regulated by the RLA, “the Act is wholly inexplicit as to the scope of allowable self-help.” Trainmen, 394 U. S., at 391; Burlington Northern, 481 U. S., at 447-448. Such silence does not amount to a congressional imprimatur on all forms of postnegotiation self-help. It does, however, indicate that we' should hesitate to imply limitations on all but those forms of self-help that strike a fundamental blow to union or employer activity and the collective bargaining process itself. Accordingly, just as we saw no statutory basis for limiting the secondary activities of unions during a period of self-help in Trainmen and Burlington Northern, we see no basis in §2 Fourth for prohibiting the crossover policy employed by TWA once bargaining had reached an impasse. Both self-help measures fall squarely within the “full range of whatever peaceful economic power [the parties] can muster” once they have “unsuccessfully exhausted the Railway Labor Act’s procedures for resolution of a major dispute . . . .” Trainmen, supra, at 392. Neither measure prevented the scheme of the RLA from working; neither measure was inherently destructive of union or employer activity. Similarly, we see nothing in Railway Clerks v. Florida East Coast R. Co., 384 U. S. 238 (1966), so heavily relied upon by the Union, that is to the contrary. In Florida East Coast we recognized a carrier’s ability to depart from the terms of an existing collective bargaining agreement when reasonably necessary to operate during a strike. As the Union itself concedes, see n. 1, supra, nothing in the collective bargaining agreement or any poststrike agreement between TWA and IFFA prohibits the crossover policy adopted by TWA. Thus, there was no departure from the collective bargaining agreement that would require an examination of reasonable necessity.
  IV
  Neither the RLA itself nor any analogies to the NLRA indicate that the crossover policy adopted by TWA during the period of self-help was unlawful. Rather, the decision to guarantee to crossovers the same protections lawfully applied to new hires was a simple decision to apply the preexisting seniority terms of the collective bargaining agreement uniformly to all working employees. That this decision had the effect of encouraging prestrike workers to remain on the job during the strike or to abandon the strike and return to work before all vacancies were filled was an effect of the exercise of TWA’s peaceful economic power, a power that the company was legally free to deploy once the parties had exhausted the private dispute resolution mechanisms of the RLA. Accordingly, the judgment of the Court of Appeals is
  Reversed.
  The Union has abandoned as irrelevant arguments that persuaded the Court of Appeals below, based on its holding in TWA I, that the union security clause of the prestrike collective bargaining agreement had survived the strike. Brief for Respondent 4, n. 6. We agree that this concession by the Union is proper. Nothing in the prestrike collective bargaining agreement guaranteed reinstatement of striking flight attendants to positions occupied by junior crossovers.
  Our affirmance in TWA I of the judgment that the union security clause sanctioned by 45 U. S. C. § 152 Eleventh survived the strike means that crossover and new hires continue to bear the burden of paying union dues. Free riding on the benefits that may come to these employees as a result of IFFA’s status as the flight attendants’ exclusive bargaining representative is thereby foreclosed. See Machinists v. Street, 367 U. S. 740, 760-762 (1961).
choices: case did not arise on cert or cert not granted federal court conflict federal court conflict and to resolve important or significant question putative conflict conflict between federal court and state court state court conflict federal court confusion or uncertainty state court confusion or uncertainty federal court and state court confusion or uncertainty to resolve important or significant question to resolve question presented no reason given other reason