(Bloomberg) — President Barack Obama hadn’t even made it

home from climate talks in Paris when Republicans in Congress

voted to kill the regulations backing his carbon-cutting pledge.

Obama’s foes want to undercut any climate accord from the

United Nations summit in Paris, along with his credibility on

the issue. But just as with the Republicans’ failed attempts to

kill Obamacare, the efforts are likely to run aground over

constitutional and legal constraints.

Even a Republican successor in the White House would have a

hard time overturning whatever commitments are made in coming

days or the U.S. power plant rules that underlie Obama’s pledge

and were targeted by Tuesday’s resolutions, now facing an

almost-certain veto.

“The Republicans might get some political talking points by

saying this, but realistically, there’s no way they are going to

repeal these rules if the courts uphold them,” said Brian Potts,

a Foley & Lardner LLP attorney specializing in Clean Air Act

cases.

The White House has pushed an approach in Paris that

ensures any final deal won’t hinge on a ratification vote in the

Senate. Unlike other international accords, it would not be

subject to the chamber’s “advice and consent.” Individual

countries’ carbon-cutting commitments are not expected to be

legally binding, and in the U.S., Obama is relying mostly on

executive branch regulations to fulfill a promise to pare

emissions at least 26 percent below 2005 levels over the next

decade.

Power Plan

That includes the Environmental Protection Agency’s Clean

Power Plan to throttle carbon dioxide emissions from the power

sector, effectively blocking construction of new coal-fired

power plants.

But Obama still needs Congress to go along with his promise

to deliver $3 billion into a United Nations fund to help

developing countries adapt to rising seas and other impacts of

climate change. And scores of lawmakers have told the president

they won’t pay the bill.

“Congress ultimately holds the power of the purse,”

according to a letter to Obama last month from 37 U.S. senators,

including Republicans John Barrasso of Wyoming and Jim Inhofe of

Oklahoma. “Congress will not allow U.S. taxpayer dollars to go

to the Green Climate Fund until the forthcoming international

climate agreement is submitted to the Senate for its

constitutional advice and consent.”

Joined by Senators Joe Manchin, a Democrat from coal-rich

West Virginia and Roy Blunt, a Republican from Missouri, Inhofe

is also pushing a resolution insisting that any climate

agreement shall have no force in the U.S. — and no money spent

to support it — unless the pact has been submitted to the

Senate for a vote.

The Obama administration has asked Congress to deliver the

first $500 million of the climate aid already. Appropriators are

negotiating an omnibus spending bill for fiscal 2016 that may

reject the request.

Congressional Weapon

The climate finance pushback is the most powerful weapon

Congress has to undercut a deal, said Steven Groves, a

specialist on treaties who is a fellow at the Heritage

Foundation, a Washington research group that favors small

government.

“The deal here in Paris completely hinges on whether

developing countries get the assurances that the money will be

coming,” Groves said.

Obama struck a confident tone before leaving France on

Tuesday, saying the U.S. will deliver the funding over time.

“This is not just one slug of funding that happens in one

year,” he said at a news conference. “This is multiyear

commitments that, in many cases, are already embedded in a whole

range of programs that we have around the world. And my

expectation is that we will absolutely be able to meet our

commitments.”

Obama’s opponents are trying to stoke skepticism in France,

where representatives from 196 countries are attending a

conference outside the capital scheduled to run through Dec. 11.

Republican congressional staff are joining conservatives there

in a bid to convince international negotiators that U.S.

financial commitments are on shaky ground back home.

French Perspective

There are signs the strategy isn’t working. Laurent Fabius,

the French foreign minister who is presiding over the climate

talks in Paris, said he discussed the U.S. politics of the issue

with Obama over dinner earlier this week. The House vote to

nullify EPA power rules “wasn’t a great surprise,” Fabius told

reporters at a briefing Wednesday. “We know the position that

the Congress has — or at least the position of many of the

Republicans in Congress.”

Fabius noted recent opinion polling that shows both

Democrats and Republicans in the U.S. are “becoming aware of how

serious the issue is.”

Senate Majority Leader Mitch McConnell, a Republican from

Kentucky, has warned that Obama’s promises in Paris “would rest

on a house of cards of his own making,” in an opinion piece in

the Washington Post Nov. 27. Even if Obama’s signature

environmental regulation — the Clean Power Plan — survives

court challenges from 27 states and a phalanx of other groups,

“the next president could tear it up,” McConnell wrote.

The threat, echoed by Inhofe in a white paper issued

Tuesday and by Republicans on the campaign trail, isn’t

realistic, regulatory specialists say.

“There is an effort by Congress to throw water on what

President Obama is doing, but at the 30,000-foot level, none of

what Congress can do or is doing is going to derail anything

going on over there,” said Rob Barnett, a senior energy policy

analyst with Bloomberg Intelligence. “It’s harder to roll back

regulations than some people would like to imagine.”

Absent a court ruling against the EPA rules, he said, “you

really have to go in and modify the Clean Air Act, and I think

there is very little appetite for doing that.”

State Compliance

States also may be well on their way to complying with the

Clean Power Plan by the time court challenges to the regulation

are resolved. Lawyers following the matter expect the

regulation’s fate ultimately will rest with the Supreme Court.

In rolling out the carbon dioxide emission limits for new

power plants and the Clean Power Plan for existing facilities,

the EPA cast the measures as essential to safeguard public

health and the environment.

Even a future administration is somewhat bound by that

justification, said Potts, the lawyer specializing in the Clean

Air Act.

“If EPA comes out with a big rule and says this is

necessary to protect public health and air quality,” he said,

“it’s really hard for the next administration to do a 180”

without running afoul of a law blocking agencies from “arbitrary

and capricious” actions.

Most of the Republicans seeking to replace Obama in next

year’s election are vowing to reverse an environmental agenda

they say would harm the U.S. economy. New York real estate mogul

Donald Trump and Senator Ted Cruz of Texas question whether

there’s even a problem.

“There is no way any reasonable person can conclude that

the most immediate threat we face to our security is what the

climate is going to look like in 25 or 30 years,” Florida

Senator Marco Rubio said at a town hall in New Hampshire.

Jeb Bush, who touts his record of land conservation and

watershed restoration as a former Florida governor, says the

climate is changing and humans may be contributing to it. But

he’s also wary of EPA regulations that may slow economic growth

and has vowed to stop Obama’s carbon dioxide emissions rules.

Bush told reporters in Waterloo, Iowa on Monday that he was

“uncertain” he would have even attended the summit in Paris.

The opening for the next president comes if courts rule

against the EPA power rules, which would put Obama’s successor

in control of determining the response.

“If it does get remanded back to the EPA — which I’d say

is at least a coin flip odds — the president gets the way in,”

Barnett, with Bloomberg Intelligence, said. “If it’s a Democrat,

they probably re-propose something very similar. If it’s a

Republican, I don’t think they can walk away from the issue.

They can’t just say ’we won’t do anything,’ but they’ll drag

their feet and do something maybe more friendly to industry.”

To contact the reporter on this story:

Jennifer A. Dlouhy in Washington at jdlouhy1@bloomberg.net

To contact the editors responsible for this story:

Jon Morgan at jmorgan97@bloomberg.net

Elizabeth Wasserman