Congress is expressly given the power to declare war (Const. Art. I, § 8, ¶ 11), and this grant of power is exclusive. The executive department, although it is charged with the foreign relations of the government, cannot declare war, but a state of war may exist without being declared, and the president may employ the military and naval forces of the United States in repelling invasion before any declaration of war has been made by Congress, or in suppressing insurrection. One of the incidents of a state of war is the seizure of the enemy's property and vessels, and it has been held that the seizure of vessels of a hostile power, as prizes of war, may lawfully take place although war has not been declared. (See Prize Cases.) However, as the money for the support of the army and navy must be appropriated by Congress, there is no practical danger that this country will be engaged ia war for any considerable length of time without a recognition by Congress of the existence of war.