To those who scorn art 1 Sec 8. If any part of the constitution is ignored, then the whole of it is ignored.
Aside this, if these lands were intended for the sole ownership of the federal government, then why are they MANAGED AS A TRUST? There would be no need for any such management by the federal government.
The trust notion is in fact the key. They can not hold any lands, by may manage them as a trust.
They have violated that trust, so therefore it no longer is in effect. All the states have to do is fire them, and take over that land and manage it as they see fit.