they simply acknowledge that the public interest requires that a coequal, branch of Government “afford Presidential confidentiality the greatest protection consistent with the fair administration of justice,” ibid., and give recognition to the paramount necessity of protecting the Executive Branch from vexatious litigation that might distract it from the energetic performance of its constitutional duties. These separation-of-powers considerations should inform a court of appeals’ evaluation of a mandamus petition involving the President or the Vice President. Accepted mandamus standards are broad enough to allow a court of appeals to prevent a lower court from interfering with a coequal branch’s ability to discharge its constitutional responsibilities. See Ex parte Peru, supra, at 587 (<HOLDING>); see also Clinton v. Jones, supra, at 701 (“We
recognizing that the government  must demonstrate the reasonableness not only of its litigation position but also of the agencys actions   holding that to grant a writ of mandamus a court in the exercise of its discretion must be satisfied that the writ is appropriate under the circumstances recognizing jurisdiction to issue the writ because the action of the political arm of the government taken within its appropriate sphere must be promptly recognized and    delay and inconvenience of a prolonged litigation must be avoided by prompt termination of the proceedings in the district court holding that a remand should be limited to cases in which further action must be taken by the district court or in which the appellate court has no way open to it to affirm or reverse the district courts action under review holding that the federal action at issue must be authorized