It was perhaps inevitable that Donald Trump would stand on the White House lawn to proclaim that the United States was quitting the Paris Agreement, our best hope ever for tackling climate change. It’s also plausible that the United States will not actually withdraw.

Like so many others, I was distressed at the images and words coming from the Rose Garden earlier this month. Having attended the 1992 Earth Summit where the global climate effort was born, spent years helping negotiators navigate their way to the 2015 Paris Agreement, and rallied companies to support the United States staying in, I could hardly bear to watch.

Trump was spurning fellow world leaders, the chief executives of many of the world’s largest companies, and a strong majority of Americans — for no evident reason other than to gratify his voting base, or simply to prove that he could.

The ensuing global outrage won’t quickly subside. Nor, let us hope, will the groundswell of renewed climate commitment. Country after country has reaffirmed its support for Paris, and a spontaneous ‘We Are Still In’ campaign by US cities, states and companies offers hope that the United States can still get close to its Paris goal. The message from many is clear: forget Trump, we’ll do it without him.

It is better, I think, not to count him out yet.

Trump did not declare a clean break from the global climate effort. The United States remains a party to the United Nations Framework Convention on Climate Change, the treaty underlying the Paris Agreement. (It also did when president George W. Bush rejected the 1997 Kyoto Protocol; had the United States not stayed then, Paris would probably never have emerged.) And the earliest the country can technically depart the Paris Agreement is 4 November 2020.

In the meantime, Trump says he is willing to rework the deal. That opening, if properly navigated, could produce another dramatic proclamation, this one keeping the United States in.

The greater obstacle may be our own visceral aversion to letting Trump ‘get his way’.

To be clear, the basic terms of Paris are not open for renegotiation. Other countries regard them as a sensible balancing of national interests against an urgent common threat. And they are weary of accommoda­ting the vagaries of US climate politics. After all, this agreement, like the Kyoto Protocol, was designed largely to US specifications.

But there is a way to preserve the core agreement and still allow the president to declare that he’s secured a better deal.

A fundamental feature of the Paris Agreement is that countries’ individual contributions are “nationally determined”. Although the accord discourages parties from weakening their goals, it doesn’t forbid them from doing so. If President Trump doesn’t like former president Barack Obama’s target of shrinking greenhouse-gas emissions to 26–28% below 2005 levels in 2025, he’s free to change it.

Although many are loath to encourage a move so clearly contravening the spirit of the Paris Agreement, some of the countries most vulnerable to climate change openly acknowledge the option. Thoriq Ibrahim, environment and energy minister for the Maldives and chair of the Alliance of Small Island States, said, “If the US wishes to change its contribution, that would be unfortunate but is its prerogative”.

Why would the Maldives or anyone else be open to a weaker US target? For the same reasons so many of us worked so furiously to persuade Trump to stay in. For now, his announcement may have a galvanizing effect. But over time, the formal exit of the world’s largest economy risks corroding global ambition.

Today’s strong momentum to decarbonize can be only a start. We need a wholesale transformation of energy and transportation systems over the coming decades to even approach the Paris goal of keeping warming below 2 °C above pre-industrial levels. Countries will make their best efforts only if they’re confident that others, especially major competitors, will too. That’s how Paris works: by strengthening confidence that everyone’s doing their part.

If the United States walks away, other countries will remain, but they’re likely to be less ambitious in meeting their initial targets, and in the next ones they’re due to set in 2020. Staying in, on the other hand, would also encourage US action by forcing a national conversation every five years around climate goals and measures. Better, on the whole, for the United States to be in than out.

How would this benefit Trump? The president has shown that he’s motivated more by the ‘deal’ than its substance, and that his extreme opening positions are just that. In the international realm alone, he’s retreated from his threat to quit the North American Free Trade Agreement, his promise to move the US embassy from Tel Aviv to Jerusalem, his currency-manipulation charges against China, and his dismissal of the North Atlantic Treaty Organization as obsolete. With his Rose Garden speech, Trump checked one box and drew another. He fulfilled his campaign pledge to leave Paris, and he told Americans he’s now going for a better deal. Coming back with a reduced target could be enticing precisely because it would allow him to claim another win.

The forces within the administration that goaded him to withdraw would no doubt persist. But the greater obstacle may be our own visceral aversion to the idea of letting Trump ‘get his way’. Our choice, in the end, may be between indulging a prideful charade or letting the United States leave. I, for one, hope we manage to keep Paris whole.

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Kaia Diringer