Does congressional authority to regulate interstate commerce (or intrastate commerce that affects interstate commerce) authorize the bailout?
That would be one way of looking at it. The other is to ask just what would part of the Constitution or law preclude Congress from performing the bailout.
"If you look through your scope and see your shoe, aim higher."
-- said to me by my 11 year old daughter before going out for hogs 8/13/2011