ASHINGTON, Nov. 17 — In the last two months, the Bush administration has proceeded with several regulations, legal settlements and legislative measures intended to reverse Clinton-era environmental policies.

These include moves to allow road- building in national forests, reverse the phaseout of snowmobiles in national parks, make it easier for mining companies to dig for gold, copper and zinc on public lands, ease energy-saving standards for air-conditioners, bar the reintroduction of grizzly bears in the Northwest and, environmentalists say, make it easier for developers to eliminate wetlands.

Environmentalists are angered that in some cases the administration, in the name of national security, is taking steps that they say promote the interests of timber, mining, oil, gas and pipeline companies, at the expense of the environment.

"They've used the smoke screen of the last two months to make key decisions out of public view," said Philip E. Clapp, president of the National Environmental Trust. "The most difficult situation we face is that the attention of the media is almost exclusively on Afghanistan and anthrax."

Most notable, critics say, is the administration's renewed advocacy of drilling for oil in the Arctic National Wildlife Refuge in Alaska. As President Bush said last month, "The less dependent we are on foreign sources of crude oil, the more secure we are at home."

Senator John Kerry, Democrat of Massachusetts, said the administration's view that oil drilling in Alaska was a matter of national security represented a "false patriotism."

"I certainly think that the re- emergence of the Arctic drilling is a direct effort to capitalize on events," Mr. Kerry said. "And it's a misplaced definition of patriotism to use Sept. 11 as a rationale for doing something that has no impact on price or dependency or immediate supply."

Administration officials say that while national security is a paramount concern, it is not their only argument for reversing many policies enacted by President Bill Clinton. They defend the changes as a way to balance what they said was an extreme tilt in favor of the environmentalists during the eight years of the Clinton presidency.

"Many of the things we have done are to put in place common-sense approaches that we feel are a better balance," Gale A. Norton, the secretary of the interior, said in an interview on Friday. "They better involve local people in decision making; they are based on cooperation rather than conflict. Our push for involving state governments in the decision-making process, our push for negotiated solutions, our push for tailoring decisions to particular areas of land are all based on philosophy, not on a wartime situation."

But both sides in the environmental debates say that the political balance changed after Sept. 11.

"In the past, you had to make an environmental argument to deflect an environmental criticism," said Scott Segal, a lawyer and lobbyist in Washington for several industrial concerns. "Since Sept. 11, it is possible to articulate an energy-security rationale that can offset environmental criticism. In comparison to security issues, criticism premised on environmental protection begins to sound parochial and not selfless."

Before the attacks, environmentalists seemed to have political momentum in casting President Bush as unfriendly to the environment and his administration as beholden to the extractive industries. But in the last two months, environmentalists have been stymied for fear of appearing unpatriotic or even petty in the face of a national crisis.

For example, the administration has ordered the United States Coast Guard to fortify its patrol of coastal waters, a duty that makes it less able to enforce antipoaching rules, leaving species like rockfish, Atlantic salmon and red snapper vulnerable. Environmentalists have remained silent, though before Sept. 11 they might have complained loudly.

Administration officials insist they are still protecting the environment. Ms. Norton said her department was starting a program to help individual property owners protect endangered species. Mr. Bush's Environmental Protection Agency is battling his Energy Department's plan to weaken standards for air-conditioners. And while this administration has been more responsive to governors of Western States than the Clinton administration was, it has not always pleased them.

Just this week, Dirk Kempthorne, the Republican governor of Idaho, said at a public hearing that he was so frustrated over federal cleanup plans on a toxic Superfund site that he was "on the verge of inviting the E.P.A. to leave Idaho."

The Bush administration has also decided to adhere to the Clinton administration proposals for limiting arsenic in drinking water. Some environmentalists thought the Bush administration should have called for lower levels, but by setting the same amount as proposed by Mr. Clinton, it defused the issue.

But the administration has let slide other matters that environmentalists argue are vital to protecting air and water quality. These include a global pact on climate change and a plan to reduce power plant emissions.

Senator James M. Jeffords, the Vermont independent who is chairman of the Environment and Public Works Committee, is advancing his own plan to require power plants to reduce four major pollutants. The administration opposes it, in part on national security grounds, saying the changes could disrupt power supplies because they might force the closing of coal-burning plants.