They fight and die to bring freedom to people around the world. It seems odd they wouldn't fight to bring freedom back to us, especially since they have family members suffering under the new communist rule here, too.
"Freedom" is relative, and what our politicians are doing on our nation-building excursions is exporting two-party politics with a public vote. This "system" is used because it mollifies the public into a sense of control (when it doesn't really have significant control), and providing justification to the elites for any action they decide is in their personal best interests.
Age-old tension between the powerful and the stupid. If the stupid people think they are free, then the stupid people won't rebel.
Anyway, forceful objection to the direction of the federal government will be cast as revolution, and the military will serve its masters, the politicians and generals. The military serves the elite, not the public, and certainly not the revolutionaries.