---   p. 19 a   ---

Complete war powers

One of the powers expressly given Congress is to provide for the common defense and general welfare of the United States while the President is made commander-in-chief of the Army and Navy and of the militia of the several States when called into actual service.{15} These powers, together with that of Congress to declare war, to raise and support armies, complete the general war powers of the government. They may be exercised to execute the laws of the Union, suppress insurrection, and repel invasions; and on military principles invasion may be repelled, as was illustrated by our experience in the war of 1812, the Mexican war, and the war with Spain, either by awaiting the enemy here or carrying hostilities into his own country.