Re: LOLWUT?

Yes, like semiautomatic and automatic fire and other such superficial differences. ;-)

Oh, surprise, you can blame Clinton for the ban on assault weapons! "I've never seen a deer in a kevlar vest"

Uh, excuse me, we trained a lot of the older Taliban fighters ourselves,

"Mom, you bore one Alexander. Here, every man is an Alexander."

In 2001, many veterans of the 80s resumed their alliance with the USA, some taking up arms again and some by joining the Northern Alliance. But many of them were still using the same weaponry they used in the 80s. It was not improper, because without superpower involvement, weaponry didn't modernize much. But even though Afghanistan has been at war in one form or another since the 1970s, only with Soviet and American/Nato presence has weaponry been kept at the cutting edge.

There is also another small issue: they fight insurgency. Insurgent armies are hard to transplant to other areas; but conversely they have the advantage on their own area. No matter how much intelligence on the ground the US/Nato collect, the insurgents will always have that advantage. The Soviets understood it, eventually. And that doesn't come from any training.

Moreover, our gov't no doubt keeps tabs on all the militia idiots, so they'd know exactly who to target in the event of an uprising by said militia(s).

And the militia movement got stronger because of Waco. What was Newton's Third again?

But your real mistake is in modelling what counts as victory or defeat.

The US might be losing less people and nominally remains in control of the ground in Afghanistan. That, under normal theory, is a victory. But it is not really looking to conquer Afghanistan or force it to accept a disadvantageous peace treaty - which are the goals for which normal theory works. It wants to root out insurgency. By that measure, it's losing, and losing big. The Taliban do not need to inflict ten thousand casualties in a week; and do not need to permanently control any piece of ground - much less do they need to strike back all the way to US bases in the Gulf. So they do not need to have the same weapons capability.

I openly think the Taliban is winning - because of what I just said.

Compare Iraq: Saddam lost, because the USA had a conventional goal, and control of the ground against the Iraqi Army did matter. It was when the insurgency broke out that victory seemed to become elusive. (And yet, with a more modest goal - to leave the new Iraqi government able to fight it, rather than to defeat it decisively before transfer; the situation improved.)

So, back to mainland America.

Are the militias, plus gun-owning Americans of all kinds, capable of standing up to the US Armed Forces?

If you want them to take on a conventional war, then no. There is no match for the US Armed Forces - on earth.
(Although some countries have some strengths that would allow them to resist better, but that's another issue)
But why would a conventional war be needed?
An insurgency within the USA would not be rooted out.
It would only need to weaken control of the US government sufficiently to make it ineffective, not to literally march through to Washington and take it like it would have been needed from a French army in 1759, from a British army in 1780 and 1812, from a Mexican army in 1846, from a Confederate army in 1861 or from a Japanese army in 1941.
If the government became ineffective enough in some area, then yes, the insurgency would likely take on governmental functions, but it would probably remain flexible enough to go back to the maquis if a counteroffensive meant it had to. That is the whole strength of the Taliban (and of all lengthy insurgencies there have been)!

So yes, it is very well viable.

Remember, fighting standing armies of standing governments is like punching walls. Fighting insurgencies is like punching water. ;)