In any case, I don't think federal military forces should ever be deployed on the mainland without the full agreement of local mayors and governors. There's a reason that's stipulated very specifically in the Constitution, that policing is left to the States.
First, I don't mean to alarm you on this point, given your many years of Constitutional scholarship, but the limits on Federal policing power are as alive today as the dodo bird. Since at least 1964 and the explanation behind the power to implement controls over private business in the civil rights act (the expansive, almost limitless view of the commerce clause), the Fed has had the power to regulate, control, police and prosecute almost every violation of state law. Ask the Rodney King cops prosecuted twice.
Second, since the Fed has almost limitless power to regulate highways (interstate commerce) and businesses (interstate commerce), it can enforce restrictions on any activity that significantly hinders interstate commerce. We have this view that policing is still local. Why, I have no idea. The Fed took over policing in Mississippi, Alabama, Arkansas, etc. in 1963, 1965, 1957 related to integration. Literally, took over everyday policing. Because they can.
Third, your view on the 10th Amendment is 100% at odds with dozens of Federal laws over the past 100+ years. For example, the Supreme Court found Constitutional federal laws penalizing the interstate transportation of lottery tickets (
Lottery Case (
Champion v. Ames), 188 U.S. 321 (1903)), of women for immoral purposes (
Hoke v. United States, 227 U.S. 308 (1913)), of stolen automobiles (
Brooks v. United States, 267 U.S. 432 (1925)), and of tick-infected cattle (
Thornton v. United States, 271 U.S. 414 (1926)), as well as a statute prohibiting the mailing of obscene matter (
Roth v. United States, 354 U.S. 476 (1957)). It affirmed the power of Congress to punish the forgery of bills of lading purporting to cover interstate shipments of merchandise (
United States v. Ferger, 250 U.S. 199 (1919)), to subject prison-made goods moved from one state to another to the laws of the receiving state (
Kentucky Whip & Collar Co. v. Ill. Cent. R.R., 299 U.S. 334 (1937)), to regulate prescriptions for the medicinal use of liquor as an appropriate measure for the enforcement of the Eighteenth Amendment (
Everard’s Breweries v. Day, 265 U.S. 545 (1924)), and to control extortionate means of collecting and attempting to collect payments on loans, even when all aspects of the credit transaction took place within one state’s boundaries (
Perez v. United States, 402 U.S. 146 (1971)). More recently, the Court upheld provisions of federal surface mining law that could be characterized as “land use regulation” traditionally subject to state police power regulation (
Hodel v. Virginia Surface Mining & Recl. ***’n, 452 U.S. 264 (1981)). Basically, Congress has the power to regulate ANY activity which affects interstate commerce, including travel, obstruction of roads, destruction of businesses, etc.
Fourth, the Federal government also has the power to protect and punish any assault on its property or personnel.
Fifth and finally, your statement that the Fed cannot send in troops unless the governor and/or mayor agrees is, frankly, bizarre. Did Orville Fauvus agree with Federal troops at Central High School in Little Rock, Arkansas from 1957-58? So a governor or even some ****** small-time mayor can override the power of the Federal government? Huh, must have missed that day in law school.
P.S. Your concerns about the extensive use of Federal power beyond what was granted by the Constitution is something I warned about in 1985, during Constitutional law class. I warned the panoply of liberals in class that "your guy" may not always be in charge.