During the first half-century of its independence, the United States participated in sixty treaties, but only 27 published executive agreements. At the beginning of the Second World War, there were about 800 treaties and 1,200 executive treaties. During the period 1940-1989, the nation entered into 759 contracts and issued 13,016 executive contracts. In total, in 1989, the United States was parties to 890 contracts and 5,117 executive contracts. In relative terms, in the first 50 years of its history, the United States has twice as many treaties as executive agreements. In the fiftieth anniversary from 1839 to 1889, there were more executive contracts than contracts. From 1889 to 1939, almost twice as many executive contracts were entered into as contracts. Between 1939 and 1993, executive agreements accounted for more than 90% of international agreements concluded.439 A significant increase in the presidency in this area was first highlighted in President McKinley`s government. At the beginning of the war with Spain, the President announced that the United States would be bound by the last three principles of the Paris Declaration for the duration, a course that, as Professor Wright points out, “would undoubtedly go a long way to defining these three principles as an international law, mandatory for the United States in future wars.” 473 Hostilities with Spain ended in August 1898 with a ceasefire, the terms of which largely determine the subsequent peace treaty,474, as well as the ceasefire of 11 November 1918, largely determine the conditions for final peace with Germany in 1918.

It was also President McKinley who, in 1900, relied solely on his sole authority as commander-in-chief, brought a 5,000-strong ground force and a naval force to work with similar contingents of other powers to save the beijing legations from boxers; A year later, without consulting Congress or the Senate, he accepted for the United States the protocol for compensation for boxers between China and the intermediate powers.475 Commenting on the Beijing Protocol, Willoughby quotes with his consent the following remark: “This case is interesting because it shows how the force of circumstances has forced us to adopt European practice in reference to an international agreement. which, with the exception of the issue of compensation, was almost exclusively political in nature . . . . Purely political treaties are usually concluded in Europe only by the executive, within the framework of constitutional practice.