The War Powers Resolution Declaration of war by the United States

in 1973, following withdrawal of american troops vietnam war, debate emerged extent of presidential power in deploying troops without declaration of war. compromise in debate reached war powers resolution. act defined how many soldiers deployed president of united states , how long. required formal reports president congress regarding status of such deployments, , limited total amount of time american forces deployed without formal declaration of war.

although constitutionality of act has never been tested, followed, notably during grenada conflict, panamanian conflict, somalia conflict, persian gulf war, , iraq war. exception president clinton s use of u.s. troops in 78-day nato air campaign against yugoslavia during kosovo war. in other cases, president asserted constitutional authority commit troops without necessity of congressional approval, in each case president received congressional authorization satisfied provisions of war powers act.

on march 21, 2011, number of lawmakers expressed concern decision of president barack obama order u.s. military join in attacks of libyan air defenses , government forces exceeded constitutional authority because decision authorize attack made without congressional permission. obama explained rationale in two-page letter, stating commander in chief, had constitutional authority authorize strikes, limited in scope , duration, , necessary prevent humanitarian disaster in libya.