This story was originally published by Mother Jones and is reproduced here as part of the Climate Desk collaboration.

“Don’t worry, be happy.”

Those were the only four English words Russian President Vladimir Putin said at a St. Petersburg International Economic Forum last Friday, reacting to President Donald Trump’s decision to withdraw from the Paris climate agreement the day before.

Trump indeed has given Putin plenty of reasons to not worry and be happy. His chaotic presidency has only alienated the U.S., destabilized traditional alliances, and helped to strengthen Russia’s position internationally, and his withdrawal of the world’s biggest economy from the fight against climate change has given Putin yet another advantage. The future of the Paris climate change agreement is now more uncertain than ever, which throws more obstacles in the way of transitioning to renewables. France’s environment minister went so far as to warn that the U.S. and Russia could be the “axis of mass destruction” by advancing fossil fuels interests at the expense of global stability.

But as unique as this historic moment is, in many ways, Putin has been here before.

Trump is Putin’s fourth American president and Paris is his second massive climate agreement. The Russian leader is neither as overt nor as consistent in his climate change denial as Trump, but he’s long played the contrarian to cast doubt on the science and seriousness of the issue. What distinguishes him from Trump is his unpredictability; Putin has always lagged behind the world’s pulse on climate change, yet he hasn’t actively disrupted international agreements in the way the U.S. has. Instead, he’s capitalized on the instability, especially when the U.S. has either retreated or completely reversed itself on climate change.

Following the news that Trump intends to withdraw the U.S. from its Paris climate commitments in four years’ time, Putin has continued his longstanding tradition of hedging his bets in relation to American leadership around this issue.

Putin speculated (in Russian) at the St. Petersburg meeting about the roots for Trump’s dissatisfaction.“Maybe the current president thinks they are not thought all the way through,” he said, while continuing to offer Russian support for the agreement. He took the opportunity for some humor about climate science at the American president’s expense. “I should say that we should be grateful to President Trump because today in Moscow, I hear they’re saying it snowed and it’s raining here, very cold, so now we can blame him for that and the American imperialism,” he reportedly said, as some in the audience laughed and applauded.

Other Kremlin officials struck a tone somewhere between lukewarm support and outright skepticism about the future of the accord, which entered into force last fall and which Russia has not yet ratified. Putin’s deputy prime minister reaffirmed Russia’s commitment to eventual ratification, but other Kremlin aides have gone further to suggest that Russia may reevaluate its position. According to NewsweekRussian state media reported one aide saying, “It is perfectly evident that without the participation of the United States, the Paris Agreement will be unworkable, because the United States is one of the biggest generators of emissions.”

At times he has called it a great threat, and at others he’s dismissed the science and the seriousness of the consequences, but what does the Russian leader really think of climate change? How have his responses shifted over the years? And are they predicated on who happens to be president as much as anything else? Experts note if he has one basic approach it’s this: Putin tends to capitalize on the chaos of global climate politics, and Trump’s presidency presents him with a golden opportunity to do just that.

“I think there’s a lot of uncertainty on how they will play it,” says Andy Bruno, a Russia environmental historian with Northern Illinois University. “It’s a good assumption that they will try to use whether they agree to join Paris or not for geopolitical leverage for other issues.”

Russia is a petrostate; its economic growth since the Soviet era has been driven by high prices in oil and gas production. With vast fossil fuel production, it ranks fourth globally in greenhouse gas emissions, after China, the U.S., and India; number one in the especially potent greenhouse gas, methane; and third among major countries in per-capita carbon emissions. Its reliance on oil and gas and interests in expanding drilling into the Arctic give Russia reason to stall on the world’s pledges to phase out fossil fuels and its subsidies.

In 2000, when the former KGB spy was less than a year into his presidency, he hosted President Bill Clinton in Moscow for World Environment Day. At that time, 192 countries had participated in the 1997 Kyoto Protocol that capped nations’ carbon emissions, but many had yet to ratify, including the U.S. — though there was still hope it would finally sign on. The two leaders issued a statement on their commitment to tackling global warming, and Clinton addressed the Russian legislature: “I hope we will be working closely together on this. In the years ahead in the Kyoto climate change treaty we committed ourselves to tie market forces to the fight against global warming … I’m pleased that President Putin and I have agreed to deepen our own cooperation on climate change.”

Russia’s commitments turned out to be in name only. Because of the timing of the fall of communism during 1990 — which was the year used by the United Nations climate framework used as its benchmark — Russia committed itself to particularly weak climate targets. But whatever minimum level of cooperation the two nations had on global warming, it didn’t last long.

Less than a year later, in 2001, the Bush administration, caving to pressure from the fossil fuel industry, declared the Kyoto Protocol “dead.” One unintended consequence was that in doing so, Bush launched Russia into a pivotal role for ensuring that the agreement crossed the threshold of the support of 55 countries representing 55 percent of global emissions it needed to go into force.

His former economic adviser Andrei Illarionov — a climate change denier himself who went on to work for Washington’s libertarian Cato Institute — says Putin’s aides “did very, very extensive work trying to understand all sides of the climate debate” in the early 2000s. Illarionov’s said this review led Putin’s government to believe that humans played a limited role in global warming, which defies mainstream science.

By September 2003, it appeared that Russia would also refuse to ratify the Kyoto agreement. At the 2003 World Climate Conference in Moscow, Putin ambiguously suggested climate change isn’t a serious problem. “They often say, half-jokingly and half-seriously, that Russia is a northern country and if temperatures get warmer by two or three degrees Celsius, it’s not that bad — we could spend less on warm coats and agricultural experts say that grain harvests would increase further,” Putin said. “That may be so, but we must also think about the consequences of global climate change.”

But Russia was famously part of the breakdown in the Copenhagen negotiations of 2009, the first climate deal of Obama’s presidency, even as it remained among the bloc of nations that wanted to see Kyoto continue, thanks to its weak expectations for the country compared with other nations that sought a new framework. The change came in 2004, when Russia did ratify Kyoto with the proviso that European members approve Russia’s participation in the World Trade Organization. Illarionov framed Putin’s decision as a straight transaction having little to do with the environment. “Everybody who was speaking [at the Russian government meeting] was saying that we do understand that the Kyoto protocol does not have any scientific background, and we are making this decision not because the Kyoto protocol is scientifically proven but because we would like to have good relations with Europe, with European countries.”

Six years later, at what was arguably the peak of the world’s rallying behind climate action in Paris, Putin abruptly shifted his tone. “Climate change has become one of the gravest challenges humanity is facing,” he said that December. “Caused by global warming, hurricanes, droughts, floods, and other anomalies are the source of economic damage.” He claimed that Russia “has been contributing actively to addressing global warming. Our country is taking the lead.”

That wasn’t technically true — analysts called the country’s pledges “inadequate” — yet his strong rhetoric still took observers by surprise. “We didn’t really know where they stood for a lot of the year leading up to Paris, because frankly they were very quiet,” says Andrew Light, a senior fellow with World Resources Institute and a former State Department climate official. Many were surprised that Russia did not play a spoiler role in the Paris talks. The thinking went that Putin saw where the politics of the issue were headed and decided to come under the banner of climate action so as not to be seen as isolated.

This year, he’s downplaying the role humans play in global warming, the Paris Agreement, or whether climate change is even a problem. “The warming, it had already started by the 1930s, that when there were no such anthropological factors such as emissions and the warming had already started” Putin said in at an Arctic forum in March. “Those people who are not in agreement with opponents [of climate change] may not be at all silly,” he continued, arguing that the world should “adapt” rather than try to stop it. Two months later, Putin, echoing a long-time climate denier point that warming could prove beneficial, told CNBC: “Climate change brings in more favorable conditions and improves the economic potential of this region.”

His swings on climate science don’t surprise environmental historian Bruno, who noted the outsized role fossil fuels play in Russia’s politics and economy. “Putin is going to be as much of an environmentalist as Rex Tillerson, former CEO of ExxonMobil, is,” Bruno says. “Tillerson had started a climate policy at ExxonMobil and said that the U.S. should remain in Paris, but is deeply committed to burning fossil fuels for the maximum profit of the company. Putin is deeply committed to burning fossil fuels for the sake of the Russian economy.”

As I’ve written before: The U.S.’s withdrawal on Kyoto “shifted the power dynamics across the world and gave Russia, which signed the agreement, greater leverage in international affairs.” Its retreat on Paris will do the same, no matter what Putin’s end goal is.

“I can imagine that [Putin’s] not displeased with what Trump is doing by trying to take measures to destabilize the agreement,” says Light, the former State official under Obama. It could help Russia’s efforts to see its sanctions lift, expand Arctic drilling, and extend its influence. U.S. isolation on climate is “going to hurt the U.S. with respect to other countries sitting down and negotiating on anything the U.S. is interested in,” and in turn, Trump is “creating a vacuum in parts of the world where we have very clear security interests, not just climate, but security in North Africa, the Middle East, and Southeast Asia.”

If Putin’s intent is to have international coalitions reverse or stall on strong climate change goals, he may see the U.S. action as moving towards the creation of a formidable bloc of states that may now stand in the way of collective action. “One thing that many of us are worried about, for example, is [how] a combination of the U.S. under Trump and Saudi Arabia and Russia could really block progress in forums like the G20,” Light says, noting that the G20 has become more proactive on climate change in the past few years, for example in their promise to phase out fossil fuel subsidies.

Or Putin may continue the approach he used in Kyoto, by making trades to compensate for U.S. inaction, promising climate commitments so countries relax sanctions on Russia or adjust foreign policy to advance Russian interests.

There is the actual possibility that instead of being alarmed at the prospect of global warming, he truly is looking forward to it because it could potentially make offshore drilling more accessible in the oil-rich Russian Arctic, a key area for continued growth of its oil and gas industry. Russia, or any country interested in stalling a transition from fossil fuels to renewables, has a lot easier time if the leader of the world’s biggest economy is causing chaos.

“They didn’t want to be isolated,” Light says, “and now they don’t have to be.”