Originally Posted by Tempest

The key word is "war". Only the congress can declare war.. The President can use the military though. i.e. North Korea etc. were "police actions". Thus congress passed the War Acts Resolution. It's true that it may be unconstitutional, however evey president to date has followed it while at the same time wording things in such as way as to not agree that it's constituational. There are also legal scholars that feel that any military action taken without congressional approval is unconstituational but that hasn't been resolved either.

Section 4 contains the 48 hour part.