Why didn't even 1 lawyer of Obama's know about needing a congressional declaration of war before bombing Libya?

The Obama administration is headed by a lawyer and filled with lawyers, and yet they presumably did not know that the War Powers Act specifically says, “The constitutional powers of the President as Commander-in-Chief to introduce United States Armed Forces into hostilities, or into situations where imminent involvement in hostilities is clearly indicated by the cirstances, are exercised only pursuant to (1) a declaration of war, (2) specific statutory authorization, or (3) a national emergency created by attack upon the United States, its territories or possessions, or its armed forces.” And it is clear that not one of the three cirstance explicitly named by the Act applied to the situation of our attack upon Libya.