Can the President of the USA disband the entire military if he wants?
That would take an act of Congress, I believe. The President is Commander-in-Chief, but Congress controls the actual forming and funding of our armed forces.
Likely any attempt to do so unilaterly would result in the president’s near-instant impeachment, unless he was very quick at taking it back.
Presidents can be impeached if the HoR thinks they brok the law. It’s a formal indictment, with the Senate as the jury. So, are you sure that disbanding the military is against the law?
I think the OP’s point is, does the President in fact have the legal right to do this?
According to Article I, Section 8 of the Constitution of the United States, the powers of Congress include the powers
which implies that such a decision would rest with Congress.
Title 5, Part I, Chapter 9, of the United States Code prohibits the President from abolishing an executive agency or department without an act of Congress. Title 10, Subtitle A, Part I, Chapter 2, Sec. 111 says,