CROW AGENCY, Mont. — The pale yellow halls of the Crow government building are nearly empty these days, with 1,000 of this tribe’s 1,300 employees recently laid off.

Across the way, Rebecca Ten Bear Reed and her children have no running water. And past the nearby grassy hills, families live a dozen to a home, playgrounds have fallen to tatters, and this tribe of roughly 13,000 people is now turning to President Trump’s promise to revive coal for its future.

“This is the worst I’ve ever seen it. Ever,’’ said the tribe’s chief executive, Paul Little Light, explaining that revenue had dwindled as the Crow’s main resource fell from favor. “A lot of people are not Trump fans here. Very few. But we would be his best friends if he brought back coal.’’

When thousands of Native Americans converged near the Standing Rock Indian Reservation last year, their stance against the Dakota Access oil pipeline became a global symbol of indigenous opposition to the pro-drilling, pro-mining agenda that Trump adopted.

But some of the largest tribes in the United States derive their budgets from the very fossil fuels that Trump has pledged to promote, including the Navajo in the Southwest and the Osage in Oklahoma, as well as smaller tribes like the Southern Ute in Colorado. And the Crow are among several Indian nations looking to the president’s promises to eliminate Obama-era coal rules, pull back on regulations, or approve new oil and gas wells to help them lift their economies and wrest control from a federal bureaucracy they have often seen as burdensome.

The president’s executive order Tuesday, which called for a rollback of former president Barack Obama’s climate change rules, is a step toward some of these goals.

At the tribes’ side is Ryan Zinke, who as the new interior secretary is charged with protecting and managing Indian lands, which hold an estimated 30 percent of the nation’s coal reserves west of the Mississippi and 20 percent of known US oil and gas reserves.

In a recent interview, Zinke noted that he was once adopted into the Assiniboine and Sioux tribes, and said he would help native nations get fossil fuels to market.

“We have not been a good partner in this,’’ he said. “The amount of bureaucracy and paperwork and stalling in many ways has created great hardship on some of the poorest tribes.

“A war on coal is a war on the Crow people,’’ he continued. “President Trump has promised to end the war.’’

Stripped of other resources, many tribes have had to rely on pit mines and oil pads to fund their budgets. This has bred conflict within not only Indian nations, but also among friends and families, with people torn between revenue that feeds their children and a deep commitment to protecting the environment.

Complicating the matter is the coal market. Although Trump has promised to revive the industry, power plants across the country are switching to cheap natural gas, leaving no guarantee that his policies will bring money back into tribal bank accounts.

“Unless there is severe restriction of natural gas production, there is not much US coal can do to expand its market in the US,’’ said Ian Lange, director of the mineral and energy economics program at the Colorado School of Mines.

Under the Trump administration, some native nations are asking for help as they work toward other revenue streams, including renewable energy. Others are seeking greater control of their own land, so they can create their own rules on harmful activities related to development, like gas flaring and wastewater dumping.

“It’s about sovereignty,’’ said Mark Fox, chairman of the Mandan, Hidatsa, and Arikara, a tribal nation north of the Standing Rock reservation that has seen a boom in oil and gas.

On the 2.3-million-acre Crow Indian Reservation in southern Montana, at least half of the tribe’s nonfederal budget comes from a single source: a vast single-pit mine at the edge of the reservation, called the Absaloka, which sends brown-black coal by rail to Minnesota’s largest power plant.

Obama’s Clean Power Plan, which called for coal-fired power plants to reduce emissions, threw the future of the Absaloka mine, and the Crow budget, into question, said Kenneth Brien, the tribe’s energy director. Already, coal revenue has dwindled, contributing to the tribe’s current economic crisis.

“I want to make this clear: Obama was a great president,’’ Brien said. But his energy policies, he said, “would have devastated the tribe.’’

One of the first tests of Trump’s commitment to coal could come in his administration’s response to the Navajo and Hopi, who derive millions of dollars from a coal-fired power plant nestled amid red rocks in Arizona, as well as an associated mine.

In February, operators of the plant voted to shut it down at the end of 2019. The move could leave 1,885 people without work, the Navajo say.