You cannot just take over the State, this is not some third world country. The Fema people cannot just bust into the state and take over like Hitler. We are 50 States not a Monarchy.
I understand your reasoning here, but in a national emergency the Federal government can override state authority. If the President were to declare a state of insurrection, then he could send in federal troops without violating the law. This is an extraordinary situation, one in which the federal government has a duty to do precisely what governments are established to do, protect and defend. This is not some fascist or third-world scenario, it's a basic element of the social contract.
One would think they did not understand our form of government.