The Good, the Bad, and the Ugly is actually a really awful film. The plot is slow and ponderous, the Italian actors are not very good (the dubbed voices are especially bad), and there is a lot of senseless violence. But this is why everyone loves this film.
The War Powers Act or War Power Resolution was the first law passed intending to define and limit the powers the President of the United States possessed.
Not to be annoyingly pedantic, but what you're thinking of is actually the War Powers Resolution, which was passed in 1973 (there were two War Powers Acts passed during World War II, but those are different, though many people refer to the War Powers Resolution as the War Powers Act, which gets a little confusing).