By Paul Rogers, San Jose Mercury News

Two months after taking office, President Barack Obama signed a historic wilderness bill that banned logging, mining and oil drilling across 2 million acres of scenic federal lands, including the Sierra Nevada, wildflower meadows on Oregon’s Mount Hood and vast vistas of California desert.

But today, with less than one week until Election Day, the environment as a campaign issue is as quiet as some of those remote landscapes.

“When you are looking at a high unemployment rate, most voters are not concerned about saving the planet,” said Barbara O’Connor, director emeritus of the Institute for the Study of Politics and the Media at Sacramento State. “They are much more interested in the economy and jobs — and whether they’ll have a pension or health care.”

Yet despite its relatively low profile this year, there is a Grand Canyon of difference between Obama and his challenger, Mitt Romney, on environmental issues, from public lands to climate change.

Since taking office, Obama has mostly sided with environmental groups, approving new regulations to limit pollution. Romney has criticized those actions as burdensome on industry and costly to consumers and taxpayers. On Romney’s campaign website, there are policy positions for 26 major issues. “Environment” is not on the list.

During the past four years, Obama has:

Approved several major new air pollution laws, including strict limits on mercury pollution and smog that

drifts between states.

Doubled the gas mileage rules for cars, copying California’s greenhouse gas standards to require the U.S. auto fleet to average 54.5 mpg within 12 years.

Set the U.S. Environmental Protection Agency on course to require mandatory limits on greenhouse gases from new power plants by next year.

Included $90 billion in the 2009 stimulus bill for energy projects, doubling wind and solar energy nationwide.

Romney has opposed all of those measures.

“I think the EPA has gotten completely out of control for a very simple reason,” Romney said in an appearance on Fox News during the GOP primary fight. “It is a tool in the hands of the president to crush the private enterprise system, to crush our ability to have energy, whether it’s oil, gas, coal or nuclear.”

Environmental groups say Obama did as much as he could, given opposition to new environmental rules from Republicans in Congress.

“I’d give the president a B-plus — and Romney an F,” said Michael Brune, national executive director of the Sierra Club, based in San Francisco. “He hasn’t even made an effort to discuss any strategy to clean up our air and water or use energy more efficiently.”

Obama has established four new national monuments, including one at Fort Ord in Monterey County. He tightened offshore oil-drilling rules after the BP blowout in the Gulf of Mexico. He defended the Clinton administration’s “roadless rule” banning logging in millions of acres of national forests. And he appointed leading scientists to top posts, including Monterey Bay Aquarium Research Institute director Marcia McNutt to run the U.S. Geological Survey and Lawrence Berkeley Laboratory director Steven Chu as energy secretary.

In one major area, however, environmentalists remain bitterly disappointed.

In 2009, then-House Speaker Nancy Pelosi pressured Democrats to pass a bill regulating greenhouse gas emissions that most scientists say are contributing to global warming. But the bill — which would have imposed a cap-and-trade system on major polluters similar to California’s — died in the Senate when key Democrats from coal and oil states balked, including Louisiana’s Mary Landrieu and Robert Byrd of West Virginia.

Environmental groups say Obama did not fight hard enough. And they remain frustrated that climate change hasn’t been an issue in the campaign, particularly in a year with historic U.S. droughts and wildfires.

“Truth be told, after the health care bill, they lost an appetite for another heavy lift,” said Larry Schweiger, president and CEO of the National Wildlife Federation. “I give Nancy Pelosi enormous credit, but when the bill got to the Senate, it was clear there was not a lot of interest and engagement from the White House.”

Critics of new climate laws, however, say green groups are out of touch with an American public that suffered during the recession, and they look warily at rules that could raise electricity or gas prices.

“The Obama administration is worried about the perception in certain states that there are people who believe environmentalists take their jobs — in mining states, in logging states, places that make cars,” said Kenneth Green, resident scholar in energy and the environment at the American Enterprise Institute, a free-market think tank in Washington, D.C.

Over time, some of Romney’s views on environmental issues have changed.

As Massachusetts governor a decade ago, Romney opposed new offshore oil drilling, pushed for tax credits for hybrid cars and expanded recycling laws. In 2003, he denied a request from a coal plant in Salem for more time to meet toxic air pollution rules.

“If the choice is between dirty power plants or protecting the health of the people of Massachusetts, I will always come down on the side of public health,” he said then.

This fall, however, his campaign has launched a full-throated defense of the coal industry, which has been hurt by cheap natural gas and tougher EPA rules. “We have 250 years of coal. Why wouldn’t we use it?” Romney said in one ad, flanked by Ohio coal miners.

On climate change, Romney said he believes the science but is concerned over the costs of curbing coal and oil. “I think it’s getting warmer,” he said in an interview last year. “Two, I believe we contribute to it. And three, I don’t know by how much — a lot or a little. And so I am not willing to adopt multitrillion-dollar programs to reduce greenhouse gases in America. They don’t call it America warming; they call it global warming.”

In the end, whoever wins Nov. 6 will have to deal with opposition in Congress, lawsuits and other challenges.

“People making voting decisions based on environmental and energy issues are going to be disappointed when the governance begins,” said Frank Maisano, a spokesman for Bracewell & Giuliani, a Houston firm that lobbies on behalf of refineries and utilities. “You usually can’t govern the way you campaign.”