Should the U.S. formally declare war on ISIS?

Senator Rand Paul (R-KY) recently proposed declaring war against the Islamic State (ISIS). The declaration would give the President more authority to carry out broader attacks on the militant group without Congressional approval. Opponents argue that the order would give the President too much power by eliminating Congressional oversight. Proponents argue that fighting an organization like ISIS requires an unconventional war plan that requires the President to make quick decisions without Congressional oversight.