And you are unwilling to accept the fact that “for the erection...and other needful buildings” is a clause that describes what may be done rather than a limiting clause that prohibits any other use.
Since you are fighting so hard to assert the collectivist or squatters rights and are fighting so hard to abandon the rights of private property owners to use their land as they see fit, I can only assume from your arguments that you are a socialist and a Marxist. As such, we have little to no common ground. Further since you have failed to refute any of the facts, it makes no sense to spend further effort in any attempt to educate you.
Wow... It explicitly states “for the erection of”. This isn’t just a prefatory clause that gives an example, this is a subordinate clause that modified the operative clause and establishes exactly the scope of it’s reach.
FEDERAL property cannot be “private”. Your conflation of the two is idiotic. It’s your assertion that the Federal collective has individual Rights is that “Marxist” stance here...
There are no "private property owners". I provided you with anecdotal evidence, above.
AND FURTHERMORE - in the lower 48, "private property owners" rent their land from the state that "their" land is in. Just refuse to pay the King's Rent for a couple of years, and find out really fast who actually owns "your" property.
The BLM is on a long term pogrom to eliminate such encumbrances.