Originally Posted by Rangermoore

Maybe this will clear up your question... Basically the President has 90 days without getting approval from congress. He just has to "Notify Congress within 48hrs"

The War Powers Resolution of 1973 (50 U.S.C. 1541?1548) was a United States Congress joint resolution providing that the President can send U.S. armed forces into action abroad only by authorization of Congress or if the United States is already under attack or serious threat. The War Powers Resolution requires the president to notify Congress within 48 hours of committing armed forces to military action and forbids armed forces from remaining for more than 60 days, with a further 30 day withdrawal period, without an authorization of the use of military force or a declaration of war. The resolution was passed by two-thirds of Congress, overriding a presidential veto.

http://en.wikipedia.org/wiki/War_Powers_Resolution