It says they have the power to "establish Post Offices and Post Roads."
Article I.8.17
To exercise exclusive Legislation in all Cases
whatsoever, over such District (not exceeding ten Miles square)
as may, by Cession of particular States, and the Acceptance of
Congress, become the Seat of the Government of the United
States, and to exercise like Authority over all Places
purchased by the Consent of the Legislature of the State in
which the Same shall be, for the Erection of Forts, Magazines,
Arsenals, dock-Yards, and other needful buildings;
Article IV.3.2
The Congress shall have Power to dispose of and make
all needful Rules and Regulations respecting the Territory or
other Property belonging to the United States; and nothing in
this Constitution shall be so construed as to Prejudice any
Claims of the United States, or of any particular State.
I don't recall Arizona's Constitution, but I do know that Nevada, when granted Statehood, ceeded (sp?) ALL lands not already owned or incorporated into towns/cities (not many back in the 1860's eh?) back to the Federal Gov't. So the BLM "owns/manages" +/- 85% of all the land in Nevada. We go out shooting in the desert ALL the time. Safely too. National Parks are a no-no. Nat'l Forests, OK... just play it safe, safe, safe... cause a lot of people seem to enjoy the trees/shade/hiking/camping, etc... wouldn't be prudent to violate their rights/life, liberty, pursuit of happiness...
So, perhaps the Feds do have the right/power to "roll up" and see that all is well... ya think?