The power to declare war is primarily considered an executive power in many countries, including the United States, where the President serves as the Commander in Chief of the Armed Forces. However, in the U.S. system specifically, the authority to formally declare war is vested in Congress, a legislative power.
So in the U.S., while the President can initiate military action, only Congress has the power to officially declare war. This division reflects a system of checks and balances between the legislative and executive branches. In summary:
- In many contexts, it's an executive power (President's role).
- In the U.S., it is ultimately a legislative power (Congress's role to declare war).