I'm pretty sure this is just a piece of legislation to justify the actions taken against Osama Bin Laden this month in Pakistan. There won't be a WWIII, even our senators and reps aren't that stupid.
Besides, the President haven't the power to deploy and use troops isn't new. War Powers Act in the 1960's gave Prez the power to deploy and utilize the armed forces for 60 days without the approval of Congress, and then after 60 days another 30 days to remove the troops. 90 days unwarranted use. It only takes a couple days to start a war, so if Americans Preisdents wanted to start wars in the past, they would have by now.
Also @ President using troops against his own people, it's been done before. President Eisenhower deployed federal troops to Little Rock, Arkansas to ensure integration. They have the power to use troops against us, it's just when we elect them we trust they'll use it for good rather than evil. So far it's worked.