Which entity has the exclusive power to declare war?

The correct answer is that Congress holds the exclusive power to declare war, as outlined in Article I, Section 8 of the United States Constitution. This section specifies that only Congress can make decisions regarding war, emphasizing the framers' intent to limit executive power and ensure that such significant decisions undergo broader deliberation and consensus among elected representatives. The rationale behind this allocation of power is to provide a system of checks and balances, preventing any single branch of government from unilaterally engaging the country in armed conflict.

While the President serves as the Commander-in-Chief of the Armed Forces and has the authority to direct military operations, this power does not extend to formally declaring war. This distinction reinforces the democratic principle that a decision as grave as going to war should involve the legislative branch, which represents the people's will through their elected officials in both the House of Representatives and the Senate.