was originally purchased or taken (via conquest) by the Federal government, and not by the states. When Federal territories became states, the Federal government retained ownership of some of the land, as is the right of any property owner. They rarely, if ever, took land away from a state.

I don't believe it is constitutional, nor morally right, nor smart, for the Federal government to just hand over land to anyone without compensation. It amounts to a transfer or wealth from US citizens to citizens of a particular state, and I don't believe this should happen. If a state wants Federal land, then it should pay for it, just like anyone else. There is nothing in the Constitution that says a state is entitled to free transfer of title of land from the Federal government, or from anyone else, for that matter.