PRESIDENT OBAMA’s declaration of waragainst the terrorist group known as the Islamic State in Iraq and Syria marks a decisive break in the American constitutional tradition. Nothing attempted by his predecessor, George W. Bush, remotely compares in imperial hubris.
Mr. Bush gained explicit congressional consent for his invasions of Afghanistan and Iraq. In contrast, the Obama administration has not even published a legal opinion attempting to justify the president’s assertion of unilateral war-making authority. This is because no serious opinion can be written.
This became clear when White House officials briefed reporters before Mr. Obama’s speech to the nation on Wednesday evening. They said a war against ISIS was justified by Congress’s authorization of force against Al Qaeda after the Sept. 11, 2001, attacks, and that no new approval was needed.
But the 2001 authorization for the use of military force does not apply here. That resolution — scaled back from what Mr. Bush initially wanted — extended only to nations and organizations that “planned, authorized, committed or aided” the 9/11 attacks.