Who has the power to declare war according to the U.S. Constitution?

The power to declare war is vested in Congress according to the U.S. Constitution, specifically in Article I, Section 8. This section outlines the responsibilities and powers granted to Congress, among which is the authority to declare war. The reasoning behind this allocation of power lies in the belief that decisions of such magnitude should involve representative debate and the consent of the nation's legislative body, reflecting the will of the people.

The framers of the Constitution aimed to prevent any single individual from wielding too much power regarding military action, which is why Congress, rather than the President or any other entity, holds this declaration authority. The President, as Commander-in-Chief of the Armed Forces, can direct military operations without a formal declaration of war from Congress but must seek Congressional approval for extended military engagements that go beyond the scope of immediate combat. This system of checks and balances is integral to the functioning of the U.S. government.