Final answer:
The executive branch, particularly the President as Commander in Chief, checks the power of the military, ensuring that military operations are conducted in line with national policies and legal frameworks, with oversight from the legislative and judicial branches.
Step-by-step explanation:
The executive branch affects the power of the military primarily by checking its power. As per Article II of the United States Constitution, the President holds the role of Commander in Chief, giving them civilian authority over the armed forces. This role allows the President to direct military operations and manage overall defense strategy, but does so within the framework of civilian oversight and accountability to the American people as well as to the legislative and judicial branches of the government.
Through this system of checks and balances, the executive branch does not simply give unchecked power to the military; rather, it ensures that military power is exercised in accordance with national laws and policies. For instance, the President may require the approval of Congress to declare war, thus sharing power and preventing unilateral military action without legislative support. Additionally, judicial oversight can come into play if there's a need to assess the constitutionality of military actions.