What political mechanism prevent US army commandment to launch a coup?

Question

I want to ask why throughout US history there has been no record of coup aiming to overthrow (at least temporarily) the elected government on the promise of "justice, liberty, equality, efficiency, making the country great again" etc. This seems to be happening very often in other democracies throughout the world, but even though Pentagon has a paramount role in US politics, I have never seen this happening.

Further, in US history it is well known that the president, the congress, and the supreme court is not always functioning efficiently or even cooperating. In the case of a political deadlock situation, it seems likely that a powerful populist leader or representative of powerful organization would be able to control the government via force, power and propaganda. However, aside from novel characters I have never seen this happening either. I imagine that people would have high motivation to do so.

Here the assumption is the majority of US population is educated but can be manipulated. If someone set up a situation that indicates the current government is not only dysfunctional, corrupt, but also utterly evil(for example, the president is a tyrant and the congress are full of puppets), then there will be calls for civil movements against the government. Suppose in some hypothetical situation there is strong conflict between certain government agency and the protesters, and the army is called to restore order, then the army commandor would have a strong incentive to overthrow the government, at least temporarily. But historically such examples, while rampant in other countries, is absent in US. And I am curious why.

(Update: The question no longer applies after Jan 6th's event)

Answer 1

There are two possible attempted military coups in US history: the Burr Conspiracy and the Business Plot to overthrow FDR. I will point though, while both involve military veterans, they do not involve the US military as an institution. Until WWII, the US did not have a standing army, so for most of US history a traditional military coup wasn't likely to occur because the army had very little power. In both cases, no one was found guilty and the evidence was in fact suppressed and brushed off as wild conspiracies to the public. So first, I think the US has avoided coups by making them seem absolutely impossible.

During the time period following WWII, the military became powerful and centralized enough to overthrow the government. But the way the military thinks about its role has changed, too. The military understands its oath is to protect and serve the American people, which means our elected representatives. They are firmly under civilian command and must follow the orders of the president-this is sometimes considered frustrating since generals probably do know best how to fight and win a war and thus occasionally causes conflict. The generals cannot publicly criticize or argue with the president and they will be dismissed for showing disrespect or disobedience to the Commander in Chief because he is unquestionable in charge of all final war decisions.

The US developed the concept following the WWII war crimes trials, that some orders are by definition illegal and all soldiers of all rank must disobey them. If part of the military were to attempt a coup, it would cause immediate chaos, since it is an illegal order.

Whistle blowers are considered brave and it has been the whistle blowers that have stopped these conspiracies. The whistle blowers in these conspiracies were largely politicians who were offered great amounts of power to take part and refused, so it seems there must be a strong commitment not just in the military but also among the politicians to the ideals of democracy to ensure its survival.

Allowing whistle blowers is often difficult. Edward Snowden provides an example of how difficult it really is to allow people the freedom to share confidential information if their conscience tells them they must. In many places, whistle blowing would be considered only destructive to the social order and sadly sometimes loyalty is valued over integrity. These places have a lot of corruption and are more likely to have coups.

Also, US elections have a very good record of being fairly held and thus the president is understood to be legitimate. In many nations, the elections process is corrupted and the president is thus not legitimate. Sometimes presidents will pass laws to make it so that they can be more or less be president-for-life. So when a military coup occurs against them, its often because they have severely abused the public trust. The military is answerable to the people and if the president is not a representative of the people, it may become their place to remove them from power. The dedication to a truly democratic system must start with the politicians, and thankfully for all their faults, the US has had politicians that strongly believed in democracy.