Zardnaar
Deity
Most of that 800 billion doesn't go to combat related stuff, the national guard are part-time soldiers who break easy, and the government isn't going to use nuclear weapons to suppress a rebellion.
EDIT: And maybe if people would actually take the time to study a little bit of military history, they could learn a thing or two about asymmetrical warfare.
Even if you win what are you gonna do? You would have multiple wrecked cities, millions dead, wrecked cities and that was in 1865.
USA is still in debt, you can honor that debt or default and turn your country into a war ravaged Zimbabwe.
If you're a progressive you need to put tax up just to rebuild the country in a devastated tax base. If you're a conservative you now have to occupy bthe biggest cities in the country, still in debt and you're probably not going to be able to extract tax and you're out numbered to boot.
You've also probably got an insurgency, plenty of guns and ammo in the country unaccounted for and odds are the next crop of leaders won't be much better than the last ones.