From Dictionary.com:
1.not set apart or voted for some purpose or use, as money, revenues, etc.
2.not taken into possession by any person:
A portion of the land remained unappropriated.
"Any person reading the Constitution who is not a lawyer can see that Federal land holding is limited for necessary usage for military, post offices and the land around DC to establish the capitol."
Who owned the Northwest Territory before it was divided into States?
Who owned the Louisiana Territory after it was purchased by the United States?
Who owned the Alaska Territory after it was purchased by the United States?
Who owned the Utah Territory after it was taken/purchased from Mexico?
Those territories were owned by the United States. Are you saying that was unconstitutional?
I don’t want to argue about this, there is too much on my mind to try and convince someone that obviously believes that the United States government can own any land they want and do with it what they will. When they cede control of vast tracts to whomever they choose, will you then wake up? Or will you just say “it is their land to do with what they please” as the Chinese begin mining operations on our National Parks?