In a 1903 speech at the Grand Canyon, President Theodore Roosevelt urged local officials to protect this magnificent place from development. He said, "Leave it as it is. You cannot improve on it. The ages have been at work on it, and man can only mar it. What you can do is to keep it for your children, your children's children and for all who come after you. …"

In 1908, he used presidential authority under the Antiquities Act to protect the Grand Canyon from development.

His passion for the great outdoors propelled his actions to protect wild places. But his love for the land was combined with a fierce determination to take on profiteers who were seeking to exploit public lands for private gains. He set a high bar for stewardship of America's treasures.

Today, the White House exhibits a vastly different approach toward our public lands.

Energy extraction supersedes all other priorities. This administration's stated goal is to make it cheaper and easier for energy developers to exploit resources on public lands.

National monuments, parks and other protected public lands provide us with clean water to drink, clean air to breathe, wildlife habitat and space to pursue outdoor traditions. They also provide an economic boost to hundreds of rural communities that benefit from the attraction to wild places.

Secretary of the Interior Ryan Zinke has both administrative power and a bully pulpit to encourage sound policy for a huge portion of our nation's public lands. He often professes his commitment to public land conservation, and he frequently evokes the legacy of TR. But his conservation actions have failed to match his rhetoric, so far.

Notably, Secretary Zinke launched a "review" of dozens of national monuments that have been designated since 1996. But he must know that before these monuments were designated, virtually all of them were subjected to arduous, comprehensive assessments to ensure that each place deserves protection for its natural, historical or cultural significance.

So this current review process is a solution in search of a problem - an excuse to roll back protections for national monuments. Unfortunately, this persecution is part of a concerted, unwarranted and unprecedented attack on lands that belong to all Americans.

I have had the pleasure of speaking with Secretary Zinke on several occasions. He and I share a love of our country's natural heritage, and we share similar military service. I believe he would like to honor the promises he has made to protect the nation's natural wonders.

However, despite his declared love of our outdoor heritage, he recently recommended reducing the acreage of the Bears Ears National Monument in Utah, a spectacularly beautiful place that is sacred to five tribal nations with ancestral ties to that land. He still has time to correct this recommendation before his final report is due by Thursday.

During his Senate confirmation process, Zinke supported full funding for the Land and Water Conservation Fund, which invests a small portion of offshore oil royalties in parks and public lands across the United States. But he later defended the Trump administration's proposed 84 percent cut to that program, an astonishing assault on the program.

Through a Secretarial Order, Zinke has opened up more of our national lands in Alaska for oil drilling. He also proposed oil exploration in the fragile Arctic National Wildlife Refuge and greased the skids for more oil drilling on federal lands.

To be a faithful steward of our public lands during the Trump administration will require courage and discipline, attributes that Secretary Zinke values. If he aspires to live up to the Roosevelt legacy, he will need to stand up to special interests and protect America's public lands.

The proof will be in his final recommendations from the national monument "review."

Our national monuments must be left "as is" - healthy and intact for our children's children to enjoy.

Roosevelt IV is a banker, a Vietnam War veteran, a lifelong Republican and the great-grandson of the 26th U.S. president.