Gregory Korte

USA TODAY

WASHINGTON — President Trump signed an executive order Wednesday calling into question the future of more than two dozen national monuments proclaimed by the last three presidents to set aside millions of acres from development.

In asking Interior Secretary Ryan Zinke for an unprecedented review of national monuments, Trump may force a question never before tested in the 111-year history of the Antiquities Act: Whether one president can nullify a previous president's proclamation establishing a national monument.

Signing the executive order at the Department of the Interior Wednesday, Trump called President Barack Obama's creation of national monuments an "egregious abuse use of power."

"And it’s gotten worse and worse and worse, and now we're going to free it up," he said. "This should never have happened."

​Trump's executive order takes aim at 21 years of proclamations beginning in 1996. That time frame encompasses the "bookends" of two of the most controversial national monument designations in recent history: President Clinton's Grand Staircase-Escalante National Monument in 1996 to President Obama's Bears Ears National Monument in 2016. Both are in Utah, and faced opposition from the congressional delegation and state officials.

Zinke's review could lead to a recommendation that Trump rescind, resize or modify existing national monuments, and conservation groups say the order endangers monuments that should be permanently protected because of their beauty, wildlife and vulnerability.

"This review is a first step towards monument rollbacks, which we will fight all the way," said Rhea Suh, president of the Natural Resources Defense Council. "These public lands belong to all of us."

Because each national monument designation comes with its own set of restrictions, the Trump administration could leave designations in place while also loosening the federal protections. In the executive order, Trump said national monument designations "create barriers to achieving energy independence ... and otherwise curtail economic growth."

The review could also result in a redrawing of the map to shrink existing monuments. The Antiquities Act requires that the protected area be "confined to the smallest area compatible with proper care and management of the objects to be protected."

"The Antiquities Act does not give the federal government unlimited power to lock up millions of acres of land and water, and it’s time we ended this abusive practice," Trump said, echoing a common complaint of western state lawmakers.

Zinke was careful Tuesday to say there's no predetermined outcome to his review. "Here’s what the executive order does not do: The executive order does not strip any monument of a designation. The executive order does not loosen any environmental or conservation regulation on any land or marine areas," he said. "It is a review of the last 20 years."

He said past designations have too often excluded the people most directly affected by the designations. "The local community, the loggers, the fishermen, those areas that are affected should have a say and a voice," Zinke said.

Unlike a national park, which must be established by Congress, presidents can establish a national monument by simple proclamation.

Once established, no president has ever revoked a national monument proclamation — but Congress has taken action to abolish 11 monuments throughout history.

Many more have been modified.

"There's no doubt the president has the authority to amend a monument," Zinke said at his confirmation hearing. "It will be interesting to see whether the president has the authority to nullify a monument. Legally, it's untested. I would think that (if) the president would nullify a monument, it would be challenged and then the court would determine whether or not the legal framework allows it or not."

The executive order asks for Zinke to review monuments designated over the past 21 years and provide a report within 120 days. But the report makes a special case for the Bears Ears monument — one of Obama's last official acts in office — by asking for an interim report in 45 days.

Zinke said the review applies only to national monuments of 100,000 acres or more, but the order itself also includes any national monument "made without adequate public outreach."

That could also ensnare smaller monuments that Obama designated for their cultural and historical significance. More than any other president, Obama used the Antiquities Act to recognize sites that "reflect the full story of our country" — including monuments important to the gay rights movement, Latinos, labor unions, African Americans, Japanese Americans, and women.

Zinke seemed to condemn that practice Wednesday. "Somewhere along the line, the act has become a tool of political advocacy," he said.