The overlap of contractual power through cooperation between Congress and the executive branch in international agreements is also demonstrated by the use of resolutions that approve U.S. membership in international organizations 408 and participation in international conventions. 409 Most executive agreements were concluded on the basis of a contract or an act of Congress. However, presidents have sometimes reached executive agreements to achieve goals that would not find the support of two-thirds of the Senate. For example, after the outbreak of World War II, but before the Americans entered the conflict, President Franklin D. Roosevelt negotiated an executive agreement that gave the United Kingdom 50 obsolete destroyers in exchange for 99-year leases on some British naval bases in the Atlantic. U.S. post-war diplomacy was strongly influenced by the executive agreements reached in Cairo, Tehran, Yalta and Potsdam. 435 For a time, the formal treaty – the signing of the United Nations Charter and the entry into multinational defence pacts such as NATO, LEATO, CENTRO, etc. – became once again the main instrument of US foreign policy, which quickly became clear in the 1960s, in addition to the contractual agreement or by the President`s initiative. that the nation, in one way or another, was obliged to protect that of the world itself. 436 The agitation in Congress is not much more important than the adoption of a “sense of the Senate” that “national commitments” would be made more solemn in the future than in the past. 437 The application of executive contracts increased considerably after 1939.
Prior to 1940, the U.S. Senate had ratified 800 treaties and presidents had concluded 1,200 executive agreements; From 1940 to 1989, during World War II and the Cold War, presidents signed nearly 800 treaties, but concluded more than 13,000 executive treaties.