The case of United States v. Curtiss-Wright Export Corp. et al. involved the export of arms to Bolivia during a time of political unrest. The Supreme Court ruled that the President has broad powers in foreign affairs, including the power to impose embargoes and regulate the export of arms. The Court also held that the President's power in foreign affairs is different from his power in domestic affairs, and that the federal government has greater authority in foreign affairs. The Joint Resolution passed by the Senate and House of Representatives of the United States of America in Congress assembled prohibits the sale of arms and munitions of war in the United States to countries engaged in armed conflict in the Chaco, unless the President finds that such prohibition may contribute to the reestablishment of peace and makes a proclamation to that effect. Violation of this prohibition may result in a fine or imprisonment. The case established the principle of presidential primacy in foreign affairs and the broad powers of the executive branch in matters of foreign policy. The lower court erred in sustaining the demurrers on the first point but overruled them on the second and third points. The government appealed to the higher court under the Criminal Appeals Act.

The President has exclusive power in international relations, and transactions with foreign nations require caution, unity of design, secrecy, and dispatch for success. The President's power in international relations does not require an act of Congress but must be exercised in subordination to the Constitution. Legislation that limits or impedes the United States' national powers in its dealings with other countries must be approached with caution. The lower court's interpretation of the resolution may have erred, and the court should consider long-standing legislative practices and construction placed upon the Constitution by contemporaries in determining constitutionality.

The Supreme Court upheld the lower court's decision to overrule the demurrer and allowed rejected grounds challenging the statute's validity to be reviewed. The Executive proclamation in question satisfies the requirements of the Joint Resolution, and the second proclamation revoking the first did not have the effect of abrogating the resolution or precluding its enforcement for offenses committed during the life of the first proclamation. The case is remanded for further proceedings.