So could the Illinois Gov call up their National Guard, since they are "employed " by the state and not the feds?
Yes, I think that's right - At least out west here, the gov can declare an emergency and put a lawless area under state control, and send in the Highway Patrol, state marshals, and even National Guard to maintain order. That is the natural flow of things without getting the fed involved.
Such a thing may also bring help from sister states - We often trade fire fighters and guard assets with WY and ID in big forest fires (sometimes UT, OR, WA, and CA if it is a big enough thing). I do believe our hotshots were down on that last Cali fire - so inter-state ways and means are well established.
If it is something mighty, like a natural disaster, where state assets are not available, or not enough, the gov would ask for a federal response, where the president would declare a national emergency and then the full weight comes from the fed.
I think that's how all that works...
