On Saturday, the People’s Climate March will take to the streets because “everything we have struggled to move forward in the United States is in peril,” according to the march’s organizers. But how much progress has there really been, in the United States, to reduce the impact of human activities on the climate?

What are these great accomplishments that are “in peril”? Fewer than many activists on the left, particularly supporters of President Obama, would like to admit.

In a draft of an article that will appear in the Harvard Environmental Law Review, the Harvard Law professor and former Obama official Cass Sunstein offers the rosiest possible evaluation of Obama’s legacy: “With a paralyzed Congress, the executive branch proved able, between 2009 and 2016, to use regulatory authorities to take a remarkable variety of steps to reduce greenhouse gas emissions.”

The results, he added, were “closely akin to what might have been done through aggressive congressional action.”

I’m skeptical. Despite vigorous recent attempts to greenwash his legacy, President Obama’s climate policy in his first term was largely indistinguishable from George W. Bush’s. Both fought mightily to avoid greenhouse gas regulation — Bush because he didn’t care about the issue, Obama because it was a lower priority than health care and, after the Affordable Care Act passed, because of fear of the political consequences. Only after the 2012 election did Obama show any appetite for actual emissions regulation, and by then it was too little — and way too late.

Why “too late”? Better late than never, you might think. The catch, and it’s a big one, is that regulations that came out in the second half of 2016 can be killed via the Congressional Review Act (CRA) — eliminated through a simple-majority vote of both houses of Congress, and the president’s signature. Such climate-related regulations that Obama issued exist at the whim of the Republican House and Senate — and we know the inclinations of the Republican Congress.

While the CRA threatens only regulations issued in late 2016, more worrying is the fate of any regulation that is still being litigated by the affected industries. Trump’s EPA can easily undo those regulations by agreeing to reconsider the issues being litigated and then eliminating all the aspects of the rules industry doesn’t like.

Even Obama’s “signature” issue, the Clean Power Plan, which would reduce emissions at power plants — the largest CO2 source in the United States — is at risk because of his administration’s foot-dragging.

Obama pursued policies without giving enough thought to how easily they could be undone

Obama’s climate strategy was a sound one, in short, only if he was 100 percent sure that Hillary Clinton (or another Democrat) would succeed him. Apparently, he and his staff did not recall that the last time one Democrat replaced another Democrat in the White House by election was in 1856, when James Buchanan succeeded Franklin Pierce.

Compared with both initial expectations and recent hype, there is simply far less substance to the Obama administration’s climate accomplishments than meets the eye.

That is not to say that the administration deserves no credit. Some of its victories occurred out of the limelight and deserve more attention — as in the case of the little-known Appliance and Equipment Standards Program. Through that program, dozens of standards have been issued by the Department of Energy, largely without fanfare or litigation, that reduce electricity used by everything from dishwashers to walk-in freezers. Quietly, cumulatively, and over the long haul, these standards will significantly reduce US CO2 emissions.

A second significant accomplishment was developing a measure to quantify the social cost of carbon (SCC), an estimate of how much damage each ton of CO2 emitted today will cause in the future. That is a fiendishly complicated task, but critically important for new regulations. That’s because regulations in this area must be justified by cost-benefit analysis; without factoring in the true cost of carbon, many future climate rules might not pass muster.

The Obama administration quickly set up an interagency working group to produce a uniform SCC estimate (albeit in a somewhat secretive process that did not allow for public notice and comment), and produced its first SCC values in 2010. And while Trump has already deep-sixed it by way of executive order, the value of that work will remain to be used by future administrations.

However, as important as the social cost of carbon was, only one Obama-era regulation relied on it in order to pass the required cost-benefit analysis. That regulation, methane standards for oil and gas production, is squarely in EPA Administrator Scott Pruitt’s crosshairs: Trump’s Environmental Protection Agency plans to “reconsider” all the issues the oil and gas industry did not like, which will surely result in gutting the entire rule.

Even Obama’s showpiece CO2 program, the Clean Power Plan, did not rely on SCC in order to pass cost-benefit analysis. Instead, the CPP’s cost-benefit calculation hinged on the benefits of reducing conventional pollutants, which on their own outweighed the plan’s compliance costs.

Then there is the Paris climate agreement, an amazing achievement (although it did not achieve nearly enough): 197 nations each agreed to take steps to reduce their greenhouse gas emissions. Paris would never have happened without US leadership, although it is ironic that through it, the Obama administration may end up effecting more change overseas than at home.

But now for the bad news.

A fateful delay in regulating CO2 from power plants

Lamentations over how sad it is that the Trump administration is going to kill the centerpiece of the Obama climate legacy, the Clean Power Plan, ring hollow to those of us who know the history of the CPP. You know what’s sad? How long and how hard the Obama EPA fought against imposing CO2 standards for these plants. They were fearful of the political consequences. When finally forced into doing so, the EPA finished them so late that Pruitt will hardly have to lift a finger to get rid of them by agreeing to “reconsider” the entire rule.

In 2006, the Bush EPA refused to regulate power plant emissions on the grounds that it did not have Clean Air Act authority to regulate CO2, because it was not a pollutant. That decision was challenged by a coalition of states and environmental groups, and it was in court when, in 2007, the Supreme Court, in Massachusetts v. EPA, held that CO2 indeed qualified as a pollutant under the Clean Air Act. In light of Massachusetts, the court handling the power plant case sent the EPA’s decision back to the agency, with instructions to reconsider its position. The Bush EPA ran out the clock without doing anything more, so that decision was sitting around when the Obama administration arrived.

Yet Obama’s EPA continued to sit on the issue, even though the states and environmental NGOs were pleading with the agency to start work on power plants. Only after being threatened with a lawsuit did the EPA capitulate, and not until December, 2010 — almost two years into the Obama administration — did it sign a settlement agreement. Under the terms of that agreement, the EPA would issue proposed rules for new and existing power plants by July 2011, and final rules for both by May 2012.

(Some apologists for the Obama administration have justified the delay by arguing that political attention was rightly focused in 2009 on the comprehensive Waxman-Markey climate bill — which would have established a cap-and-trade system for limiting emissions. That excuse doesn’t fly. Waxman-Markey passed the House in June 2009 and then died immediately in the Senate, with no hope of 51 votes, let alone overcoming a filibuster. More damningly, many activists had pleaded with the EPA to work on power plant regulations specifically to encourage Congress to encourage a more market-oriented approach. And of course it would have been useful to have the regulatory process well underway in the likely event that Waxman-Markey failed — as it predictably did.)

The EPA then proceeded to ignore the settlement agreement concerning power plant emissions. (Ignoring settlements was a pattern for the Obama EPA.) It did not propose standards for new plants until March 2012, and did not propose any standards for existing ones, the actual source of emissions. In response to election-year objections from the coal industry, EPA withdrew the proposed regulation and did not come up with a replacement until another 18 months had passed. EPA only got around to proposing existing plant standards — the Clean Power Plan — in June 2014, fully three years after it had promised to do so.

Because the EPA did not finish these standards until 2015, they were still being litigated when Donald Trump arrived, which makes it extremely easy for him to avoid implementing them. All of this was foreseeable. Let’s stipulate a generous four years from the start of the regulatory process to a final rule. If the Obama administration had started work in 2009, it would have been finished by 2013, and the legal challenges would have been over and done long before the Obamas left town.

Obama let slip the chance to regulate the CO2 emissions of oil refineries

And that is not the worst of it. The Clean Power Plan’s demise is small beer compared with the effect of the Obama EPA’s grossly irresponsible failure to deal with oil refineries.

First, a bit more about the Clean Air Act. Each Clean Air Act “stationary source category” — power plants, cement factories, steel mills, pipelines, and the like — has its own set of emission standards, and CAA Section 111 says that every eight years the EPA must review and, if appropriate, revise these standards.

After Massachusetts, you might think the EPA would now have to start including CO2 standards as part of that review. (Recall that the Supreme Court found that CO2 should be considered a pollutant.) However, in a 2008 decision refusing to regulate refinery CO2 emissions, the Bush EPA said that Section 111 does not require the EPA to consider CO2 emission standards in these periodic reviews.

A year into the Obama administration, the EPA agreed to reconsider the Bush EPA’s refinery decision. A year after that, the agency signed a settlement agreement committing to propose emission standards for both new and existing refineries by December 2011, and to issuing a final rule by November 2012. These would include appropriate CO2 emissions standards.

Despite the settlement, no such standards were ever proposed or finalized. More critically, in its eight years, the Obama EPA never reversed the Bush EPA interpretation that the Clean Air Act does not require that CO2 emissions must be included in the periodic Section 111 review.

With Hillary Clinton’s defeat, the opportunity to reverse that wrongheaded Bush-era decision has been lost. Unless the DC Circuit can be convinced that the Bush interpretation (now presumably the Trump interpretation as well) is wrong, any limits on CO2 from stationary sources now face a multi-year, steeply uphill slog through EPA and the courts.

The legal challenge environmentalists now face, due to the Obama administration’s unconscionable delay, is immense. Under legal rules, the DC Circuit would have to conclude not just that any EPA decision to not regulate CO2 was incorrect but that it was “arbitrary and capricious.” Anyone who has ever litigated against the EPA knows how mind-bogglingly difficult it is to overcome the great deference courts give to this kind of agency decision.

And that is how the Obama EPA dealt with the two largest stationary CO2 sources. I could go on (don’t get me started on cement kilns, or the EPA’s “best available control technology” guidance), but you get the picture.

There has been progress on car and truck emissions — but California should get the credit

Obama climate apologists love to talk about the great things done to regulate CO2 emissions from cars and trucks, but in this case, they are trying to sign his name to someone else’s work.

For cars, the only thing the EPA should get credit for was granting a Clean Air Act waiver that allowed California to set its own CO2 standards for vehicles. That was not a very heavy lift: It was a campaign promise that President Obama ordered the EPA to make good on in his first week in office. A few months later, Obama and the auto industry had a photo op in the Rose Garden, with automakers agreeing that the California standards would become the national ones.

This, however, was pure smoke and mirrors. Once EPA granted the waiver, California’s standards went into effect there and in more than a dozen other states that followed California’s lead, totaling about 40 percent of the US car market. But here’s the catch: The auto industry had already announced that it would only build a single “California-compliant” fleet for the whole country. It had already established the California standards as the de facto national ones. The much-ballyhooed federal standards merely made them officially so.

There was never much doubt that the EPA would grant a waiver for California. Such requests are almost automatically granted, and the Bush EPA had denied it on completely bogus grounds. To be sure, this was a victory for the climate, but Obama can’t take the credit.

The same holds for the second round of these standards for model years 2017 to 2025: The EPA simply adopted California’s de facto national standards. While Trump and Pruitt have made clear that they intend to ax the complementary federal standards, unless they also succeed in revoking the California waiver (legally, very difficult to do), losing the federal standards will not add a single ton to US vehicle emissions.

Obama’s defenders further maintain that the EPA and the Department of Transportation issued the first-ever truck CO2 standards in 2011 on their own initiative. Nonsense. The 2007 Energy Independence and Security Act mandated that the DOT (in consultation with the EPA and the Department of Energy) create a “fuel efficiency improvement program designed to achieve the maximum feasible improvement.” (To a rough approximation, fuel efficiency and CO2 emission standards are the same thing.) The Obama administration does, however, get full credit for a second round of more stringent standards, which it was not legally obligated to issue.

Overall, the Obama climate change legacy is weak

The Obama administration simply did not make climate a priority. While California took the lead on cars, the Obama EPA wasted enormous amounts of resources in its doomed power plant regulations by ignoring pleas to work faster. And by failing to change the Bush EPA refinery rule, they handed the Trump EPA an excellent excuse to do nothing about refineries or other “stationary sources.” And by waiting so long on other climate regulations, such as the oil and gas methane rule, they made it easy for Trump and congressional Republicans to wipe out most of their accomplishments.

Marching to promote action on climate change is a worthy endeavor. But let’s also be clear how little happened under President Obama’s watch. On this issue, history will not judge him kindly.

David Bookbinder is the chief counsel of the Niskanen Center, a libertarian think tank. He is former chief climate counsel of the Sierra Club. (Disclosure: The author represented natural gas vehicle interests during the litigation over federal emissions standards for trucks.)

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