President Obama is trying to lay the groundwork for a new international climate change agreement. Meanwhile, his counterpart Down Under, Australian Prime Minister Tony Abbott, is trying to pull the rug out from under him.

One widely cited but little-understood aspect of the EPA’s proposed regulations on carbon emissions from existing power plants is their presumed effect on the potential for a global climate deal.

Supporters of the EPA proposal argue it is a great triumph, despite its modest CO2-emission-reduction goals, because it would enable the U.S. to meet the pledge Obama made at 2009 U.N. climate talks in Copenhagen to reduce greenhouse gas emissions by 17 percent from 2005 levels by 2020. (The proposal would not get us there by itself, but we could hit the target by combining it with possible future actions like reducing methane leakage from natural gas systems.) That, in turn, would give Obama the credibility he needs to take the lead in negotiating a more ambitious global agreement to reduce greenhouse gases at the next round of talks in Paris next year. Sure enough, China, the world’s biggest greenhouse gas emitter, announced that it’s considering a cap on carbon emissions just a day after EPA released its plan.

Obviously, keeping our commitment to reduce emissions is essential to striking another deal. So EPA’s current proposal, or something stronger, would be a necessary condition to getting an agreement in Paris. But will such an agreement actually be reached?

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That’s hard to say. To understand the potential for a deal in 2015, and how these regulations might fit into it, you must first understand what happened in 2009. In December of that year, when Obama went to Copenhagen, the House of Representatives had passed the Waxman-Markey cap-and-trade bill, which would have restricted U.S. greenhouse gas emissions to 17 percent below 2005 levels by 2020. Obama helped get an agreement, known as the Copenhagen Accord, under which other countries committed to cuts of their own.

In 2010, Kerry-Lieberman, the Waxman-Markey bill’s companion in the Senate, died because it could not muster the 60 votes needed to overcome a filibuster. Without a law mandating the reductions in emissions, it looked as if the U.S. would fail to meet its Copenhagen Accord target.

But U.S. emissions declined anyway. The recession reduced economic activity. Americans started driving less. Wind and solar energy became more affordable and widely deployed. The fracking boom led to natural gas displacing some coal burning. And the Obama administration started using its authority under the Clean Air Act to require emissions reductions through higher fuel-efficiency standards for vehicles and, now, through rules governing emissions from power plants.

So does this give the international community the confidence it needs to have in U.S. leadership? Arguably, it shouldn’t. It has been demonstrated that Senate Republicans and some Democrats from fossil fuel states don’t care about climate change. Obama has been able to make a partial end run around them, and some economic factors beyond his control have helped. Still, the power-plant rules could be hung up in court challenges when Obama goes to Paris. He cannot promise to do anything requiring congressional action, nor can he guarantee that a Republican successor would meet his commitments. International treaties require ratification by two-thirds majority in the Senate. No Senate in 2016, with its rural bias and deep bench of Flat Earther Republicans, will ratify a climate change agreement.

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International energy policy experts, however, say that these are not reasons to be too pessimistic. It is possible to make international agreements other than treaties that, like the Copenhagen Accord, don’t need to be ratified by the Senate. “No serious U.S. analyst is thinking about a treaty,” says Michael Levi, director of the Program on Energy Security and Climate Change at the Council on Foreign Relations. “There are all sorts of agreements short of a treaty that are possible and don’t require Senate ratification.”

And other countries may not worry too much about the backward elements in U.S. politics. Every country has countervailing political pressures, and every government could change course, or be replaced by opponents, and yet deals are made all the time. “Even a law has no guarantee of in-perpetuity compliance,” notes Peter Ogden, director of international energy and climate policy at the Center for American Progress. “A future Congress could repeal it.”

The biggest impediment to a new global agreement on emissions reductions may come not from the U.S.’s right wing, but from our usually more progressive Anglophone allies. In the years since Copenhagen, Australia and the United Kingdom have elected conservative governments, and Canada has reelected its conservative leadership. Canada and Australia in particular are rapaciously exploiting their fossil fuel resources, and reversing the environmental progress made under previous administrations. On Tuesday, The Sydney Morning Herald reported that Australian Prime Minister Tony Abbott is trying to form an alliance of British Commonwealth countries to reject a climate agreement:

Tony Abbott is seeking a conservative alliance among “like-minded” countries, aiming to dismantle global moves to introduce carbon pricing, and undermine a push by US President Barack Obama to push the case for action through forums such as the G20.

Visiting Ottawa for a full day of talks with the conservative Canadian Prime Minister and close friend Stephen Harper, Mr Abbott flagged intentions to build a new centre-right alliance led by Canada, Britain and Australia along with India and New Zealand.

All five Commonwealth countries now have “centre-right”-leaning governments but it is Mr Abbott’s personal and philosophical closeness to Mr Harper that the Prime Minister regards as most important.

The combined front would attempt to counter recent moves by the Obama administration to lift the pace of climate change abatement via policies such as a carbon tax or state-based emissions trading.

The irony is that Australia is already suffering particularly bad consequences from climate change. It’s been hit by dramatic heat waves, wildfires, and droughts in recent years. And it’s poised to suffer more. Australia’s population is overwhelmingly coastal, and its biggest tourist attractions — Sydney’s beaches, the Great Barrier Reef — could be destroyed by climate change. Australia’s conservatives don’t care.

The EPA’s proposed emissions rules are a necessary condition to getting a new global climate agreement, but they are insufficient. More will be needed not just from the U.S. but from other major economies around the world, and Abbott’s new obstructionist campaign demonstrates how hard it will be to get wide agreement on action. But at least the U.S. won’t be the bad guy this time around.