Language in the declaration of a national emergency around border security, signed by Trump in February, directs the secretaries of Defense, Interior and Homeland Security to support operations at the border, "including, if necessary, the transfer and acceptance of jurisdiction over border lands."
Activists and Democrats have raised concerns that allowing construction on public lands could damage the ecosystem in those areas by disrupting wildlife or using resources like water that are scarce in the desert.House Natural Resources Chairman Rep. Raul Grijalva, D-Ariz., strongly criticized Trump for the decision as well.
"The Trump administration has treated our border with Mexico like a testing ground for dangerous, extremist ideas from day one, and now we see public lands being handed over to the military using the same national security excuse they always hide behind," Grijalva said in a statement. "This sends a message to the world that we are a fearful country with no sense of responsibility or proportion.""The Army doesn’t have the authority to enforce domestic laws, and anyone who believes in protecting our legal system should oppose this move and Trump’s border wall with everything they can muster," he added.
The move will become effective when a notice is published in the federal register, likely next week.