[Supermancho]

In America, it certainly isn't about who you can kill or how fast. Any individual can kill multiple individuals on a micro scale and multiply that every time a weapon kills a soldier or a soldier trades weaponry.

The US military problem would be that it has to subdue a population that has been socialized to resist (to the point that it already birthed paramilitary during the previous democracy) and constitutes the replacements for that military (and the industries necessary for supply) for coming generations. Hell, once it had a democracy the first time, it still went to civil war. Thinking about the short term doesn't get you much.

Predator drones, nukes, etc won't solve the problems that couldnt be solved in a foreign land. Domestically it would be harder and longer fought.

[whatshisface]

You're missing a giant factor here which is the possibility that the military might ally itself with an existing civilian faction in such a way that only half the country saw the coup as a power grab.

For example, let's say that the military made a deal with <insert the most extreme sub-faction of your least favorite party here>. Then they'd have people to install into the newly vacated positions of civilian economic administration, and in that, they'd have a way to motivate that faction to join them and support their legitimacy.