Yes
> Can that supply chain be made in the US and how long can will it take to make?
In a limited capacity yes but also in like 5 or so years the answer will be an unequivocal yes.
How independent would TSMC's American foundries be if cut off and forced to operate autonomously if US/China war breaks out?
I am sure that the goal is full independence but I have no idea what the current state of that is, what the state of it will be in 5-10 years etc.
Most are much smaller and more specialised/less automated so they don't have the same kind of production but there are a lot of fabs in the US and a lot of fab knowledge. Of all the countries, the US is one of the few that could probably survive a semiconductor industry collapse outside.
And many of those semiconductors in cheap FPV drones likely are actually fabbed in the US or could easily be fabbed in the US by Intel, Infineon, Texas Instruments, pSemi, NXP, Bosch, Renesas, Micron, onsemi, Analog Devices, Honeywell, Polar, GlobalFoundaries, Microchip, or Samsung, just to name a few non-military facing companies with significant fab operations in the US.