But the Constitution also gives Congress an array of war powers, including the power to “declare war,” “raise and support armies” and “make rules concerning captures on land and water.” By “declare war,” the Constitution’s framers did not mean merely firing off a starting gun. In the 18th century, war declarations were often limited in scope — European powers might fight a naval battle in the Americas, for example, but not battle on their own continent. In giving Congress the power to declare war, the Constitution gives it authority to make decisions about a war’s scope and duration.
The Founders, including James Madison, who is often called “the father of the Constitution,” fully expected Congress to use these powers to rein in the commander in chief. “The constitution supposes, what the History of all Governments demonstrates, that the Executive is the branch of power most interested in war, and most prone to it,” Madison cautioned. “It has accordingly with studied care, vested the question of war in the Legislature.”In the early days of the republic, the Supreme Court made clear that Congress could limit the president’s war powers — notably in the Flying Fish case. In 1799, during the “Quasi War,” the undeclared sea war between the United States and France, Congress authorized President John Adams to clamp down on trade between the two nations by stopping ships headed to French ports. But Adams went further, ordering commanders to stop ships that were sailing to or from a French port.
When the Flying Fish was seized while sailing from a French port — something Congress had not authorized — the ship’s owner sued. The Supreme Court decided in his favor, ruling that the president had no right to issue the order he did.
John Marshall, the nation’s greatest chief justice, declared that even in a time of hostilities, a president’s decision to act militarily beyond what Congress had authorized was “unlawful.”http://www.nytimes.com/2007/01/29/opinion/29mon4.html?_r=1&oref=slogin