... while the Treaty Clause was, in the original understanding, the exclusive way to make treaties, the Framers also apparently recognized a class of less-important international agreements, not rising to the level of "treaties," which could be approved in some other way. Article I, Section 10, in describing restrictions upon the states, speaks of "Treat[ies]" and "Agreement[s]...with a foreign Power" as two distinct categories. Some scholars believe this shows that not all international agreements are treaties, and that these other agreements would not need to go through the procedures of the Treaty Clause. Instead, the President, in the exercise of his executive power, could conclude such agreements on his own. Still, this exception for lesser agreements would have to be limited to "agreements" of minor importance, or else it would provide too great an avenue for evasion of the protections the Framers placed in the Treaty Clause.
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A more substantial departure from the Framers' vision may arise from the practice of "executive agreements." According to the Restatement of Foreign Relations Law of the United States, the President may validly conclude executive agreements that (1) cover matters that are solely within his executive power, or (2) are made pursuant to a treaty, or (3) are made pursuant to a legitimate act of Congress. Examples of important executive agreements include the Potsdam and Yalta agreements of World War II, the General Agreement on Tariffs and Trade, which regulated international trade for decades, and the numerous status-of-forces agreements the United States has concluded with foreign governments.
