Not saying it will turn out differently, but there are more guns circulating in the US than there are people. Nearly everyone has or can easily get access to a gun. US culture is also quite a bit different, celebrating violence, don't tread on me, etc...
Again, it might not make a difference, but I'm not sure those other situations are comparable.
Something else to note is that military officers swear an oath the constitution, not POTUS (like enlisted do). Asking someone to order or to shoot fellow Americans, particularly if unarmed, would definitely be a test. If something like that did happen, we would be entering a second civil war.
APCs take fuel, require men to run, and need tires or tracks. For $10 worth of chemicals or a little bit of camouflage and some earth work you can make the APC irrelevant very quickly.
Happened in Iraq all the time.
The US military and its members have spent almost 25 years fighting through insurgencies.
There are millions of combat vets.
