Stardate 20010920.0731 (On Screen): A link from last week: the question has come up in
Clueless Comments as to whether the US has made a Declaration of War. As part of an emergency budget bill last week, $40 billion was allocated partly for disaster relief and partly to fund initial military operations. The bill also contained an authorization to use force against those who were responsible for the attack.
It was not formally a Declaration of War, but it is comparable to the Gulf of Tonkin resolution, which also was not formally a Declaration of War but which was judged by the courts to have the same legal effect. In addition, under the War Powers act, the President can commit US military forces for sixty days without permission of Congress. (On the 61st day he has to either get approval or withdraw.) (discuss)