Ancient granaries, part of the House on Fire ruins, are shown here in the South Fork of Mule Canyon in the Bears Ears National Monument on May 12th, 2017, outside Blanding, Utah. (Photo: George Frey/Getty Images)

Well he did it. Secretary of the Interior Ryan Zinke, in a stunning and unprecedented move, sunk his knife into one of our oldest and most important conservation laws.

With his signature at the top, Zinke on Monday sent President Donald Trump a memo that urges him to shrink the size of the newly minted Bears Ears National Monument, a 1.3-million-acre sprawl of federal land in southern Utah that Barack Obama protected toward the end of his second term. In doing so, Zinke earns the dubious distinction of being the first Secretary of the Interior to try to rollback a national monument designation. He becomes the first Secretary of the Interior to attempt to unilaterally erode the power of the Antiquities Act, a 111-year-old law first laid down by Teddy Roosevelt and used in the intervening decades to preserve such treasures as the Grand Canyon, Devils Tower, Craters of the Moon, and, yes, Bears Ears.

Though it comes after a 45-day "review" period during which the secretary sought to project an air of studied and sober deliberation, Zinke's decision was a pre-ordained conclusion. Not even overwhelming pro-national-monument sentiment among the general public prevented him from recommending that Bears Ears be reduced in size. During a recent 15-day public comment period on the Bears Ears designation, for instance, 96 percent of all respondents expressed support for the monument, according to an analysis by the Center for Western Priorities. Public opinion, though, is piddling compared to the wealthy and powerful forces that are driving the anti-Antiquities Act agenda.

For years now, a network of dark money groups aligned with the billionaire brothers Charles and David Koch have sought to chip away at our conservation system. Alongside their political allies, they have promoted the land transfer agenda. They have undermined the Land and Water Conservation Fund. They have sought to weaken the Endangered Species Act. And, as I wrote in a piece last month, they are leading the assault on the Antiquities Act.

The two bluffs known as the Bears Ears stand off in the distance in the Bears Ears National Monument on May 11th, 2017. (Photo: George Frey/Getty Images)

More evidence of this plutocratic plotting emerged in early June. Less than two weeks ago, a slate of Koch-affiliated dark money organizations, including the American Legislative Exchange Council, Heritage Action for America, the American Lands Council, the Sutherland Institute, Strata Policy, the Competitive Enterprise Institute, and the Montana Policy Institute, among others, sent a letter to Trump urging him to "reduce and rescind egregious national monuments where local support exists to do so."

"We applaud your decision to review the national monuments designated over the past 21 years and check years of executive overreach related to federal lands," wrote the groups, many of which have received hundreds of thousands, if not millions, of dollars from conservative dark money funds tied to the Koch brothers and their billionaire allies.

Zinke, the brave Navy SEAL, buckled to their demands. Trump will undoubtedly do the same, which will set off a precedent-setting legal battle that could well destroy the Antiquities Act's effectiveness. After all, if a national monument designation can simply be rescinded according to political whim, then such a designation means almost nothing at all.

This whole mess is a shameful turn for our Secretary of the Interior. Zinke, over the course of his meteoric rise in national politics, has called himself a "Teddy Roosevelt Republican," the kind of Republican that supports conservation despite its often progressive imperatives. But his memo on Monday shows that his reverence for Roosevelt is a sham. The man who claims to represent Roosevelt's legacy is doing more than anyone in recent American history to dismantle that legacy. Roosevelt, after all, signed the Antiquities Act into law in 1906 and used that law to preserve the Grand Canyon and other monuments on behalf of the American people as whole. Zinke, for his part, is doing the exact opposite: In a bold dismissal of the American public's desires, he is trying to gut the Antiquities Act on behalf of the most reactionary special interests among us.

Zinke is nothing like Roosevelt, and history will remember him that way.