Yeah, ultimately it ends up being decided who the military is backing. Look at Spain, initially overtaken by a military coup. Then after Franco's death, as the transition to full blown democracy was already happening, sometime in the 80s (23-F), right as the successor to Suárez was about to take place, the military attempted another coup, but this time the military was on the people's democracy side, and basically saved democracy that day.

Really a hit or miss concept, military coups.

In the USA, there was never a need for a military coup. After the Spanish-American war, the MIC was so wealthy that they simply bought influence. A few million handed to influential politicians is far cheaper than a coup.

The USA has the best government that money can buy.

We had a coup attempt without military intervention on 1/6. The current regime is actively purging the military leadership.

Countries don’t have military coups or juntas because they are fundamentally bad or whatever. It happens becuase controls and civil authority is too weak, and we are in a cycle where the US is dismantling all controls and adopting a position of unlimited executive power. So it’s a matter of “when” some general intervenes. Either at the behest of someone or to save the republic.

You don’t really need a lot of people. Maybe a battalion or two.