The Fox News host's attempt to tie the president's protection of land to a sinister plot is "full Alex Jones," one outlet said.
"While darkness and denialism can hide much, they erase nothing," the president said at the ceremony.
The national monument honors Emmett Till, the Black teenager from Chicago whose abduction and killing in Mississippi in 1955 helped propel the civil rights movement.
A tribal coalition has called on President Joe Biden to permanently protect 1.1 million acres from new uranium mining and other development.
The mountain — "Avi Kwa Ame" in the Mojave language — and the surrounding landscape are rich in cultural resources and sacred to Native American tribes.
Along with designating Camp Hale-Continental Divide National Monument, he moved to ban new mining across 225,000 federal acres.
On the 116th anniversary of the landmark Antiquities Act, dozens of green groups are pressuring the administration to protect a unique landscape in West Texas.
Tribal leaders pitched Washington on their vision for a nearly 3 million-acre site to safeguard cultural resources and prevent future expansion of a military complex.
Utah's GOP delegation portrayed tribes as allies in their fight against protected national monuments, even though they petitioned for one site's creation.
Trump’s attack on Bears Ears and Grand Staircase-Escalante in Utah was the largest rollback of federal land protections in U.S. history.