Beg to differ. Any almost universal revolt by the American people against their government, which includes the military, would be unable to "take over" as long as the military stuck by the government.
Such a widespread revolt might indeed make it very difficult for the government to enforce its will everywhere, perhaps impossible if the military would be unwilling to use extreme measures. But that's a very different issue from "the people" being able to defeat the government and its military.
Your statement would have been true up to about 1939, not since.
Since military men take an oath to the Constitution, not to the government, I don't get heartburn over this. I cannot imagine any issue that would divide the people sufficiently to lead to civil war that would not also divide the military. God forbid it ever comes to this.
Such a revolt would not be against just the military. It would target the entirety of the federal government: politicians, bureaucrats, file clerks and secretaries. And without people to administer the payroll, buy ammo, and pay for stuff, the army ceases to exist
A few years back, just two men (the "DC snipers") came close to shutting down DC. Visualize the effect of a few hundred individuals deciding to become quiet serial killers of federal employees.
Put more succinctly, in the movie "Fight Club" to a certain politician: "Look, the people you are after are the people you depend on. We cook your meals. We haul your trash. We connect your calls. We drive your ambulances. We guard you while you sleep. Do NOT f**k with us."