Who has the authority to deploy the military?

Bit of a political nerd here, so I'm curious, who exactly has the power to deploy the military, both at home and abroad? I tried to Google around a bit but it seems like there's a lot of variance in the answers. Any clarity from y'all would be great.

In the United States, the power to deploy the military is shared by the President and Congress in accordance with the Constitution. The President, as Commander-in-Chief, has the authority to use the military in immediate response to threats against the U.S or its allies.

However, any significant long-term deployment generally requires Congressional approval. The War Powers Resolution of 1973 is a federal law intended to limit the power of the President to send armed forces into combat situations without the consent of Congress. It mandates that the President notify Congress within 48 hours of committing armed forces to military action and forbids the military from remaining for more than 60 days without Congressional authorization for use of military force or a declaration of war.

When it comes to domestic deployment, the Posse Comitatus Act of 1878 restricts the use of federal military personnel in domestic law enforcement. However, the National Guard can be called upon by state Governors to aid in domestic emergencies like hurricanes, floods, or civil unrest.

Ultimately, the decision to deploy the military, both abroad and at home, involves a combination of executive and legislative authorities, with built-in checks and balances to prevent the misuse of military power.