*sigh* This argument again.
1. Domestic military infrastructure is heavily dependent on civilian infrastructure. See how long tanks and planes operate without fuel.
This isn't some fantasy land, this is how we won the first revolution. When it kicked off, the continentals didn't take the red-coats head-on, they besieged Boston; and it worked.
2. Look at all the trouble we've having in Afghanistan, and then consider that Afghanistan is about the size of Texas. So if Texas and a couple other states were committed...
Nevermind economic warfare. Can you imagine what would happen to food prices everywhere if the bread-basket states rebelled? If they were leveled Russia-in-chechnya style? The public would have little stomach for civil war.
3. Our military is an all-volunteer force sworn to defend the Constitution. Not the Congress, not the President. They are not the government goon squad and if asked to fire on innocents many would defect.
You say the government could, as a matter of physics, wipe out the rebellion. Yeah, for the most Pyrrhic victory the world has ever seen. Such action would also likely only spur further rebellion.
The point is, an armed, committed, organized rebellion of multiple states could quite plausibly defeat the US military as it currently stands.