Justice Rehnquist
delivered the opinion of the Court.
The Court of Appeals for the Ninth Circuit held that § 102(2)(C) of the National Environmental Policy Act of 1969 (NEPA), 83 Stat. 853, 42 U. S. C. §4332(2)(C), requires the Navy to prepare and release to the public a “Hypothetical Environmental Impact Statement” with regard to the operation of a facility capable of storing nuclear weapons. Catholic Action of Hawaii/Peace Education Project v. Brown, 643 F. 2d 569, 572 (1980). Because we conclude that the “Hypothetical Environmental Impact Statement” is a creature of judicial cloth, not legislative cloth, and that it is not mandated by any of the statutory or regulatory provisions upon which the Court of Appeals relied, we reverse its decision.
The facts relevant to our decision are not seriously controverted. Pursuant to a decision by the Navy to transfer ammunition and weapons stored at various locations on the island of Oahu, Hawaii, to the West Loch branch of the Lualualei Naval Magazine, the Navy prepared an Environmental Impact Assessment (ElA) concerning how the plan would affect the environment. The assessment concluded that the necessary construction of 48 earth-covered magazines and associated structures would have no significant environmental impact, and therefore no Environmental Impact Statement (EIS) was prepared at the construction stage. Construction contracts were let in March 1977 and in April 1978. Construction of the West Loch facilities has been completed and the magazines are now in use. It is stipulated that the magazines are capable of storing nuclear weapons. Because the information is classified for national security reasons, the Navy’s regulations forbid it either to admit or to deny that nuclear weapons are actually stored at West Loch.
In 1978, the Navy prepared a Candidate Environmental Impact Statement (CEIS). This CEIS deals generally with the environmental hazards associated with the storage, handling, and transporation of nuclear weapons, but does not refer to any specific site or storage facility. It concludes that no significant hazards to the environment are present.
In March 1978, respondents brought this action seeking an injunction against the building of the new facilities at West Loch until an EIS had been filed. Their principal complaint was that the Navy’s EIA had ignored the enhanced risk of a nuclear accident resulting from West Loch’s proximity to three nearby air facilities, the effects of such an accident on the population and environment of Hawaii, and the effects of radiation from the storage of nuclear weapons in a populated area. The United States District Court for the District of Hawaii concluded that the “construction and use of the storage facilities at West Loch is a major federal action” within the meaning of § 102(2)(C). 468 F. Supp. 190, 193 (1979). But given certain national security provisions of the Atomic Energy Act, 42 U. S. C. §2011 et seq. (1976 ed. and Supp. IV), and the Navy’s own regulations concerning nuclear weapons, the District Court concluded that petitioners had complied with NEPA “to the fullest extent possible.” 468 F. Supp., at 193. We find it unnecessary to reach the question posed by the District Court’s reliance on the security provisions of the Atomic Energy Act, since respondents have made no showing in this case that the Navy has failed to comply, or even need comply, with NEPA’s requirements regarding the preparation and public disclosure of an EIS.
Section 102(2)(C) of NEPA, 42 U. S. C. §4332(2)(C), provides that, “to the fullest extent possible,” all federal agencies shall “include in every recommendation or report on proposals for legislation and other major Federal actions significantly affecting the quality of the human environment, a detailed statement” discussing, inter alia, the environmental impact of the proposed action and possible alternatives. Section 102(2)(C) also requires that the EIS be made available to the President, the Council on Environmental Quality (CEQ), and the public, subject to the provisions of the Freedom of Information Act (FOIA), 5 U. S. C. § 552 (1976 ed. and Süpp. V).
We have previously noted: “The thrust of § 102(2)(C) is . . . that environmental concerns be integrated into the very process of agency decisionmaking. The ‘detailed statement’ it requires is the outward sign that environmental values and consequences have been considered during the planning stage of agency actions.” Andrus v. Sierra Club, 442 U. S. 347, 350 (1979). Section 102(2)(C) thus serves twin aims. The first is to inject environmental considerations into the federal agency’s decisionmaking process by requiring the agency to prepare an EIS. The second aim is to inform the public that the agency has considered environmental concerns in its decisionmaking process. Through the disclosure of an EIS, the public is made aware that the agency has taken environmental considerations into account. Public disclosure of the EIS is expressly governed by FOIA. 42 U. S. C. §4332(2)(C).
The decisionmaking and public disclosure goals of §102 (2)(C), though certainly compatible, are not necessarily coextensive. Thus, § 102(2)(C) contemplates that in a given situation a federal agency might have to include environmental considerations in its decisionmaking process, yet withhold public disclosure of any NEPA documents, in whole or in part, under the authority of an FOIA exemption. That the decisionmaking and disclosure requirements of NEPA are not coextensive has been recognized by the Department of Defense’s regulations, both at the time the West Loch facility was constructed and today.
In an apparent attempt to balance what it considered to be the disclosure requirements of NEPA with national security interests, the Court of Appeals concluded that petitioners could prepare and disclose an EIS that would assess the impact of the storage of nuclear weapons at West Loch without revealing specific information regarding the number and type of nuclear weapons to be stored at the facility. 643 F. 2d, at 572. The EIS could hypothesize, but not concede, that the facility will be used for the purpose for which it has been made capable. Ibid. But in inventing the “Hypothetical Environmental Impact Statement,” the Court of Appeals departed from the express intent of Congress manifested by the explicit language in §102(2)(C). That language provides that public disclosure of the EIS shall be governed by FOIA. As we concluded in EPA v. Mink, 410 U. S. 73, 80 (1973), FOIA was intended by Congress to balance the public’s need for access to official information with the Government’s need for confidentiality. Of the nine exemptions in Subsection (b) of FOIA, we think two are relevant in determining whether the Navy must release an EIS. Exemption 3, 5 U. S. C. § 552(b)(3), which authorizes the withholding of documents “specifically exempted from disclosure by statute,” arguably exempts the publication of an EIS under the Atomic Energy Act. But we find it unnecessary to decide this question, because to us it is clear that Exemption 1, 5 U. S. C. § 552(b)(1), is applicable.
Exemption 1 exempts from disclosure matters that are “(A) specifically authorized under criteria established by an Executive order to be kept secret in the interest of national defense or foreign policy and (B) are in fact properly classified pursuant to such Executive order.” Executive Order No. 12065, 3 CFR 190 (1978-1979 Comp.), confers upon specified officials the power to classify information if its release would pose a threat to national security. Virtually all information relating to the storage of nuclear weapons is classified. Thus, any material properly classified pursuant to Executive Order No. 12065 is exempt from disclosure under Exemption 1, and therefore is exempt from the public disclosure requirements of NEPA.
Congress has thus effected a balance between the needs of the public for access to documents prepared by a federal agency and the necessity of nondisclosure or secrecy. The Court of Appeals in this case should have accepted the balance struck by Congress, rather than engrafting onto the statutory language unique concepts of its own making. By requiring the Navy to prepare a “hypothetical” EIS, the Court of Appeals required the production of a document that would not exist save for what that court thought to be NEPA’s public disclosure requirements. But NEPA’s public disclosure requirements are expressly governed by FOIA. In NLRB v. Sears, Roebuck & Co., 421 U. S. 132, 161-162 (1975), we held that FOIA “does not compel agencies to write opinions in cases in which they would not otherwise be required to do so. It only requires disclosure of certain documents which the law requires the agency to prepare or which the agency has decided for its own reasons to create.” See Forsham v. Harris, 445 U. S. 169, 185-186 (1980); Kissinger v. Reporters Committee, 445 U. S. 136, 152 (1980). It follows that if the Navy would not be required by FOIA to release an EIS were one already prepared, it is obviously not required to prepare a “hypothetical” EIS nowhere mentioned in NEPA.
Since the public disclosure requirements of NEPA are governed by FOIA, it is clear that Congress intended that the public’s interest in ensuring that federal agencies comply with NEPA must give way to the Government’s need to preserve military secrets. In the instant case, an EIS concerning a proposal to store nuclear weapons at West Loch need not be disclosed. As we indicated earlier, whether or not nuclear weapons are stored at West Loch is classified information exempt from disclosure to the public under Exemption 1.
If the Navy proposes to store nuclear weapons at West Loch, the Department of Defense’s regulations can fairly be read to require that an EIS be prepared solely for internal purposes, even though such a document cannot be disclosed to the public. The Navy must consider environmental consequences in its decisionmaking process, even if it is unable to meet NEPA’s public disclosure goals by virtue of FOIA Exemption 1.
it does not follow, however, that the Navy is required to prepare an EIS in this case. The Navy is not required to prepare an EIS regarding the hazards of storing nuclear weapons at West Loch simply because the facility is “nuclear capable.” As we held in Kleppe v. Sierra Club, 427 U. S. 390, 405-406 (1976), an EIS need not be prepared simply because a project is contemplated, but only when the project is proposed. To say that the West Loch facility is “nuclear capable” is to say little more than that the Navy has contemplated the possibility that nuclear weapons, of whatever variety, may at some time be stored here. It is the proposal to store nuclear weapons at West Loch that triggers the Navy’s obligation to prepare an EIS. Due to national security reasons, however, the Navy can neither admit nor deny that it proposes to store nuclear weapons at West Loch. In this case, therefore, it has not been and cannot be established that the Navy has proposed the only action that would require the preparation of an EIS dealing with the environmental consequences of nuclear weapons storage at West Loch.
Ultimately, whether or not the Navy has complied with NEPA “to the fullest extent possible” is beyond judicial scrutiny in this case. In other circumstances, we have held that “public policy forbids the maintenance of any suit in a court of justice, the trial of which would inevitably lead to the disclosure of matters which the law itself regards as confidential, and respecting which it will not allow the confidence to be violated.” Totten v. United States, 92 U. S. 105, 107 (1876). See United States v. Reynolds, 345 U. S. 1 (1953). We confront a similar situation in the instant case.
The decision of the Court of Appeals for the Ninth Circuit is reversed, and the case is remanded with instructions to reinstate the judgment of dismissal entered by the District Court.
It is so ordered.
An Environmental Impact Assessment is a document prepared by a federal agency in order to determine whether a formal Environmental Impact Statement should be prepared. See 40 CFR § 1508.9 (1981).
Navy Security Classification Guide for Nuclear Weapons, Navy SWOP 55-1 (1974); Dept, of Navy, OPNAV Instruction 5721.1C (1975).
42 U. S. C. §§2014(y), 2161, 2162, 2271.
32 CFR §214.8 (1978) (repealed).
32 CFR §214.6 (1980).
Executive Order No. 12065 superseded Executive Order No. 11652, 3 CFR 678 (1971-1975 Comp.), which in turn superseded Executive Order No. 10501, 3 CFR 979 (1949-1953 Comp.). Our decision in EPA v. Mink, 410 U. S. 73 (1973), rested on an application of Executive Order No. 10501. 410 U. S., at 81, and n. 7, 84, and n. 9.
See 32 CFR §214.8 (1978) (repealed); 32 CFR §214.6 (1980).