It is well accepted that the conduct of war is an "executive Power," vested by Article II in the President, who also serves as Commander in Chief of the Armed Forces. Both at the time of the Framing of the Constitution and afterward, there has been agreement that the President has the power to repel invasions. Intimately familiar with the treatises on international law, the Framers were undoubtedly aware of the general rule that, as Hugo Grotius had put it, "By the law of nature, no declaration is required when one is repelling an invasion." The Law of War and Peace (1646). The debate, instead, has centered on the location of the power to initiate war.