It’s against the rules.
People who won’t follow the rules are identified and weeded out of the machine before they get to command a very large force. Some
of the military rules are harsh, like killing the nation’s enemies, so a certain fraction of people can’t follow all the rules. It’s no big deal, they get discharged and go find another job.
How do you perform a coup against a piece of paper? Coups work against dictators and kings because they have absolute power. You remove a person, and you control the country. If the US President were removed by the military, the rest of the country would still continue to operate under the Constitution like nothing really happened. The commander of those forces wouldn’t gain any actual power.
A military coups in the modern US is at least theoretically possible, it’s just very highly unlikely.
The US doesn’t operate like a banana republic. High ranking military officers aren’t promoted due to direct loyalty to a dictator or due to nepotism the way things happen in 3rd world countries and in dictatorships.
The President does pick the Joint Chiefs for example, but does so by proxy and only with confirmation of the Senate. It’s not like in Russia where Putin picks all the top people and eliminates anyone he considers even remotely a threat.
The US also rotates assignments every few years so individuals and groups can’t form cliques with direct loyalty to a specific officer as easily because people rotate so often.
The US has historically been a very stable country and a strong belief in democracy is at its core so there isn’t an underlying desire to overthrow the government because if you don’t like your government in the US, you can easily vote them out.
High Ranking military officers believe in the chain of command and have an quasi-religious belief in being answerable to the civilian government.
There’s also a very strong court system in the military with strict regulations. Those that are a problem are rooted out and gotten rid of.
Government in the US is also quite decentralized. The system of semi-autonomous States vs the Federal government makes launching a coups fairly impractical.
EDIT: You also have to consider that the different branches of the US military (Army, Navy/Marines, Air Force, and Space Force) all operate independently with their own chains of command. They work together with common cause, but are notorious for inter-service rivalry, so getting more than 1 to work together for a coups would be quite the feat.
Two organizations that might actually be dangerous for launching a coups would actually be the CIA (who do that everywhere else all the time), and PMCs (Private Military Contractors aka mercenary organizations) that are very well armed and equipped and have loyalties outside the US military structure and could be loyal to a specific US leader. We saw a similar attempt at a coups in Russia with the Wagner group. It’s important to note that organizations like the CIA are forbidden from operating on US soil against US civilians but do anyway…
There are scenarios though where a would-be dictator could attempt to launch a coups. There was a disorganized coups attempt on Jan 6, 2021 albeit the military wasn’t involved.
4/5 largest air forces in the world are all within the US. A coup is generally _one_ branch of the military successfully taking control of government because they are able to obtain [keys of power](https://youtu.be/rStL7niR7gs?si=H3UORHkFi6C1KK_a). A coup in the US would be a larger battle than any other place in the world and would cause catastrophic global instability and economic ruin. Basically, there is no significant upside for _anyone_ in a coup of the US as things stand today. So nobody really wants one. There’s no real upside, even for some power-hungry general.
A coup in the US doesn’t give any legitimate power. Say the take over the white house.. Who cares, they can’t create law, they can’t sign laws, they can’t do anything. The other two branches will just tell them to ‘eff off and congress will just stop paying them.
This is one of the many beauties of the separation of powers.
*(For fear of the downvotes, this is also why the handwringing over what happened on J6 with people going into the Capitol is a little misplaced/over-the-top. Not saying it wasn’t stupid — but it wasn’t any real threat to democracy)*
The leader of the military is the President (Commander in Chief). In order for a coup to work you would need the entire military disobeying their highest ranking officer, not just one or two senior officials, as the President outranks everyone. This is theoretically possible if a president were to just absolutely lose it however the bar is super high.
The fact theres nothing to gain.
Since US didn’t get rich by running mines that can make a fortune running on dying slaves, having a coup will destroy the economy and make everyone, including the soldiers themselves, poorer.
This is generally true for developed countries, it is also why coups tend to happen in Africa where they do get rich running mines on dying slaves.
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