President Obama will announce in a major policy speech on Tuesday afternoon that he'll try to save the Earth by skipping over Congress — which has failed to pass much environmental legislation in recent decades — and use executive orders to regulate how much greenhouse gas existing power plants can produce, make appliances more efficient, increase the amount of renewable energy used on public property. The White House has been planning on Obama making this speech for weeks, The New York Times' John M. Broder reports, "But the initiative is likely to be at least somewhat drowned out by a rush of competing and compelling news" — the Supreme Court, the National Security Agency's collection of everyone's phone calls, the immigration bill in Congress. But maybe that's the point. Obama will do something about global warming at the exact moment he's having to deny that he's the urban liberal professor version of Dick Cheney.

Since the 2012 election, there hasn't been a lot of good news for Obama's liberal base. House Minority Leader Nancy Pelosi was booed and heckled at Netroots Nation when she defended the NSA's spying. Obama's nominee to head the CIA was filibustered over the drone program, and he announced some changes that could allow some Guantanamo detainees to go home after a hunger strike at the facility grew to include more half the people imprisoned there. (Some detainees are still being force-fed, and the strike is still growing.) Environmentalists have frequently protested the Keystone XL pipeline in front of the White House. Obama's speech on Tuesday, in which he will not reveal his decision on the pipeline, will give them something to seize on.

Obama's announcement comes at a time when his presidency is — yet again — being declared dead. Thanks to bad news and Washington gridlock, "Not yet six months into his second term, Barack Obama's presidency is in a dead zone," argues Politico's John F. Harris, Jake Sherman, and Elizabeth Titus. This is because of "his own failure to use the traditional tools of the presidency to exert his will. Obama does not instill fear — one of the customary instruments of presidential power." Obama might be failing at deploying an intangible instrument of presidential power, but on Tuesday, he will use a real one. New Jersey Rep. Rob Andrews, a Democrat, tells Politico, "I don’t think he has chosen to use all the levers of power that he has at his disposal." Obama relies too much on the power of his speeches, Andrews says, instead of instilling fear. But analysis might give him reason to think fear wouldn't work either: "Eighty percent of the members are in a district where a primary challenge is their principal political vulnerability... If the president goes out and barnstorms, it works politically for that member to vote against the president. It has the opposite effect." Neither perks nor a reign of terror would change that electoral reality.

Obama's piecemeal approach to slowing our descent into environmental calamity is a big change from 2008, when had big plans to stop global warming, The Washington Post's Brad Plumer explains. But cap-and-trade failed in the Senate in 2010 — before the Tea Party wave later that year. Now he's going to use a piecemeal approach to slowing environmental calamity. Obama's turning to the Environmental Protection Agency, which the Supreme Court ruled in 2007 can regulate carbon dioxide. The EPA has proposed carbon standards for future plants, but it hasn't yet targeted existing plants, which release 40 percent of carbon emissions in the U.S. Obama's announcement changes that. How tough the EPA makes its new rules will determine whether the U.S. can meet its goal of cutting carbon emissions by 17 percent of the 2005 level by 2020.

The pace at which the federal bureaucracy moves partially explains the timing. In May, New York's Jonathan Chait reported Obama's executive orders might go down like this, according to the Natural Resources Defense Council's Dan Lashof:

The agency will finish drafting its regulation scheme by the end of the year. It will then take about a year of public comments and revisions, at which point it will finalize its rule. That will be the end of 2014, just after the midterm elections. Another nine months to a year will be required to carry out the rule, which will get us to the end of 2015—and the international climate summit.

This isn't the first time the White House said it would turn to executive action to get things done. That happened only a year into Obama's first term. "The challenges we had to address in 2009 ensured that the center of action would be in Congress," White House aide Dan Pfeiffer told The New York Times' Peter Baker in February 2010. "In 2010, executive actions will also play a key role in advancing the agenda." Baker's analysis of what problems that might pose is interesting given what's happened since then:

But Mr. Obama has to be careful how he proceeds because he has been critical of both Mr. Clinton’s penchant for expending presidential capital on small-bore initiatives, like school uniforms, and Mr. Bush’s expansive assertions of executive authority, like the secret program of wiretapping without warrants.

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