The day after the November 2010 elections made clear President Barack Obama's greenhouse-gas legislation was doomed, he vowed to keep trying to curb emissions linked to global warming. There's more than one way of "skinning the cat," he told reporters.
Since then, Obama has used his executive powers — including his authority under the 1970 Clean Air Act — to press the most sweeping attack on air pollution in U.S. history. He has imposed the first carbon-dioxide limits on new power plants, tightened fuel-efficiency rules as part of the auto bailout and steered billions of federal dollars to clean-energy projects. He also has proposed slashing mercury emissions from utilities by 91 percent by 2016.
Obama's end run around Republican opposition has delighted environmentalists, but it has drawn the ire of business groups and conservatives who argue he is crippling the coal industry, driving up energy costs and hurting the overall economy.
"Environmental regulation should be about protecting public health, and not about creating green jobs and mitigating hypothetical risk," said Diane Katz, research fellow in regulatory policy at the conservative Heritage Foundation. "Being unemployed and poor from overregulation, or zealous regulation, is a greater risk than global warming."
When Obama was elected in 2008, environmentalists were confident their most-cherished goals — ending coal-fired power plants, limiting greenhouse-gas emissions and invoking new protections for public lands — were finally within reach.
Following up on a campaign promise, the president backed legislation that would slash America's carbon output by 80 percent by 2050. Under the proposed cap-and-trade legislation, companies would buy and sell emissions credits allowing them to pollute more.
The bill was passed by the House, which at the time was controlled by Democrats, but in June 2009 it was blocked in the Senate by Republicans and moderate Democrats. When Republicans won control of the House in the 2010 elections, the bill was dead.
The administration turned to the Clean Air Act, which Obama allies said the president became familiar with while serving on the Senate Environment and Public Works Committee. Using the law's extensive authority, the administration issued six major environmental rules, including ones that placed limits on toxic air pollutants, greenhouse gases, soot and smog-forming pollutants.
The strategy was bolstered by some outside factors. Its effort to limit carbon emissions was benefited by the natural-gas boom; many utilities are switching from coal to natural gas, which is more economical and emits much less carbon. The automobile bailout gave Obama the leverage to impose tougher fuel-efficiency standards, and the Environmental Protection Agency faced several lawsuits pending from the Bush administration that needed to be resolved.
Obama's standards for new vehicles, said Michael Brune, executive director of the Sierra Club, rank as "the biggest move to get us off our oil dependence by any president ever." The rules, which took effect this year, will require the U.S. auto fleet to average 54.5 miles per gallon by 2025.
Heather Zichal, deputy assistant to the president for energy and climate change, said the administration's array of environmental rules go to the "sweet spot of energy security, economic opportunity and reducing pollution," and fit into a favorite Obama theme during the 2008 campaign.
But the business community argues that the regulations are heavy-handed and are hurting the nation's economic security.
"The utility sector, which we consider a part of the manufacturing sector, has been hit extremely hard," said Ross Eisenberg, vice president of energy and resources at the National Association of Manufacturers.
Utilities, he said, are shuttering older plants and holding off expanding existing ones out of fear that the EPA will deny them permits.
Last month, urged on by several business and energy groups, the GOP-controlled House passed the Stop the War on Coal Act, which would reverse several Obama regulations and proposals. It would bar the EPA from regulating greenhouse gases, jettison the stricter fuel standards and give states primary authority over the storage and disposal of coal-combustion waste. But that bill has little chance in the Democratic-controlled Senate.
Because the administration, faced by partisan polarization, has moved ahead on its own, opportunities for compromise have been lost, some say. Eisenberg notes that during former president Bill Clinton's second term, the two parties negotiated passage of such significant environmental laws as the 1996 Safe Drinking Water Act.
"The big difference is you had a Congress and an administration a little bit willing to work together on the issues, he said.
Obama has disappointed environmentalists in some cases.
In September 2011, he decided to pull back an EPA proposal to limit ozone emissions linked to smog, on the grounds that it would hurt the economy and the government would revisit the issue in 2013 anyway. The business community praised the move, while environmentalists said it was irresponsible.
The administration also has been criticized by some environmentalists for not moving to create new wilderness areas, in which development and energy extraction would be barred. Only Congress can designate wilderness but the president can bestow similar protections by creating national monuments through the 1906 Antiquities Act.
"It's not something they're making a priority," said Heidi McIntosh, associate director for the Southern Utah Wilderness Alliance. She said administration officials have been unwilling to overrule the objections of state and local officials on several key land-use issues.
Barring a last-minute development, the current Congress will be the first since 1966 to fail to designate a single wilderness area. Obama has recently declared a few national monuments based on their historic or cultural significance, including Colorado's Chimney Rock, and has forged private-public partnerships to preserve working landscapes in states such as Florida and Kansas.
Obama has spent only a brief amount of time visiting national parks, and the National Park Service budget has declined 6 percent in the past two years.
Both Obama friends and foes agree on one thing: The president will probably pursue an even more aggressive environmental agenda if reelected.
House Natural Resources Committee Chairman Doc Hastings, R-Wash., said in a statement he would expect Obama to push for more national monument designations in a second term. "From nearly day one," he said, "the Obama Administration has attempted to impose policies that would block public access to public lands and cause significant economic harm and job loss."
When it comes to putting more public land off limits to development, he added, "Such decisions should not be made by unilateral orders from the president" using a 106-year old law.
Environmental leaders expect Obama to try to take tougher action on limiting greenhouse-gas emissions from existing power plants if reelected.
Obama hinted as much during a speech to a crowd of Colorado State University students in August.
"We're on track to emit fewer greenhouse gases this year than we have in nearly 20 years," he said. "You can keep those trends going. That all happened because of you."