The only recent example is the breakup of the Soviet Union....the various breakup nations got to keep the stuff they had on their soil.
Certain things would be hard to move: The silos in Montana, Wyoming, etc (if those states decided to secede). There aren't many chemical or bio weapons left (officially), they've pretty much all been destroyed AFAIK. Then there are issues like the nuclear waste storage facility in New Mexico, the various federal labs like Los Alamos, Sandia, Fermilab in Chicago, Jet Propulsion lab in California, etc.
Emergency Medicine - saving the world from themselves, one at a time.
"Thou shalt not be a victim, thou shalt not be a perpetrator, but, above all, thou shalt not be a bystander."
I make the ADL soil themselves. And that makes me very happy