In the United States, the president is in a unique position different than anyone else in the government. Elected by all of the people, his job is to represent the entire country even though not everyone voted for him.
Michael Swanson, The War State: The Cold War Origins of the Military-Industrial Complex and the Power Elite, 1945-1963, Kindle Edition (Michael Swanson, 2013), 15
The further away from its base on the American continent the government of the United States seeks to exert power over the affairs and relations of other countries the weaker its efficiency becomes and the further it oversteps the limits of its strength the more likely it is to lead the nation into disaster - a terrible defeat in a war in Europe or Asia beyond the conquering power of its soldiers, sailors, and airmen. If wrecks of overextended empires scattered through the centuries offer any instruction to the living present, it is that quest for absolute power not only corrupts, but in time destroys.
Charles Beard, President Roosevelt and the Coming of War, 1941: Appearances and Realities (New Jersey, Transaction Publishers 2003), 592-593