Perhaps George Washington's most significant lasting impact is that, through his actions, he set important precedents for the presidency of the United States. He was, of course, the first President, and unlike all of his successors, he had no model to look to (except, perhaps, the negative model of European monarchy.) He was also aware that his decisions would, in turn, set precedents for what the leader of a republic should look and act like. Some of his decisions while in office were very important in this respect. First, he established the Cabinet, now crucial to the operation of the executive branch. This institution is not specifically called for, or at least not outlined in any detail, in the Constitution. So when Washington appointed Secretaries of State, War, Treasury, and an Attorney General, he established a precedent that would be followed by all of his successors. Presidents would be assisted by formal advisors. Washington also began a practice of staying out of European wars that would last until the United States entered the First World War in 1917. First in his Neutrality Proclamation in response to the outbreak of war between Revolutionary France and Great Britain, and then in his famous Farewell Address, Washington asserted what would become the most important principle in American foreign policy until the twentieth century. Finally, Washington, by refusing to run for a third term, established a precedent that would be observed until 1940, when Franklin Roosevelt was elected a third time with World War II looming. This informal tradition was made law in the Twenty-second Amendment.