Sen. Elizabeth Warren (D-Mass.) in Hampton Falls, N.H., on Monday. (Brian Snyder/Reuters)
Opinion writer

For many years, people in politics thought about action on climate change the way they do about issues such as campaign finance reform: Most voters will tell you it’s something they’re in favor of if you ask them, but it isn’t at the top of the priority list for anything but a small number of them. Which means that if you run for office, win and then don’t really do anything about it, you won’t get punished.

That may have been true at one time, but as the Democratic presidential primary is showing, it isn’t any longer.

On Wednesday evening, CNN will host a seven-hour town hall on climate, featuring 10 of the candidates. In advance of the event, some of those who hadn’t yet released climate plans have done so or have updated their old ones; just in the past few days, new plans have arrived from Elizabeth Warren, Kamala D. Harris, Cory Booker, Amy Klobuchar and Julián Castro.

Looking over what they’re proposing, you might be tempted to say they’re just rushing to put something out even if they haven’t been all that active on the issue before, and there’s some one-upmanship going on. You want to spend $2 trillion? I’ll spend $3 trillion! (Though nobody’s going to beat Bernie Sanders, who says he’ll spend $16 trillion.)

But it’s important, as voters judge the candidates and their ideas, that they not get too worried about which one really, deep in their hearts, cares the most about climate change. It’s not a completely irrelevant question, but the system is operating in such a way that it’s pushing all the candidates in the same direction — and making it impossible for the one who wins to go back on what they’re promised.

Let’s take a quick overview of what they’re proposing. The details and emphasis may differ, but they all have a few things in common:

  • Rejoin the Paris climate accord and make the United States a leader on fighting climate change
  • Make significant investments in clean energy research and creating green jobs
  • Pay for it with taxes on the wealthy and/or polluters
  • Require stricter pollution controls and transition away from fossil fuels
  • Hit net-zero emissions within a few decades
  • Emphasize environmental justice so low-income and minority communities don’t bear the brunt of pollution
  • Help those who now work in the fossil fuel industry and the communities in which they live make the transition to a new green economy

That’s the basic program you’ll get with a Democrat in the White House and a Democratic Congress. And unlike on some issues, the differences between the candidates in what they want to do aren’t all that fundamental. I suppose it’s possible that there could be some vicious infighting over whether the clean-energy research fund should get $75 billion a year or $100 billion a year, but I doubt it.

If this is the most important issue to you, you’re probably disappointed that Gov. Jay Inslee of Washington dropped out of the race, because he had the most comprehensive blueprint on climate and had said it would be the driving force of his presidency. But we’ve just about reached a point of convergence after which inaction from a Democratic president will be all but impossible.

In presidential campaigns, we spend a lot of time wondering and worrying about who candidates are deep in their souls, which can be worthwhile — as the current occupant of the White House has shown, a president’s personality and character flaws can make a big difference. But there are also ways that institutional forces determine what the president does, whoever they are.

The health-care debate provides a good example of how this operates. In 2008, Hillary Clinton was the Democratic candidate who had thought most about health care and worked the longest on it. But the party’s voters demanded action, and the plans that the candidates offered were all very similar, reflecting a consensus that had evolved within the party about what the best approach was. So when Barack Obama took office, he wound up doing almost exactly what Clinton would have done if she had won.

I’m sure he cared deeply about health care. But the point is that even if he didn’t, at that moment in history, his basic decisions about what to propose and how hard to push for it were a given. The people who put him in office wouldn’t have tolerated anything else.

The same is going to be true with the next president, if that person is a Democrat. There’s a party consensus on both the urgency of climate change and the basic outlines of how to go about addressing it. The campaign, furthermore, is forcing the candidates to present plans that reflect that consensus and publicly advocate them. Even if the eventual winner secretly believed that climate should be a lower priority that could wait until a couple of years into his or her term, he or she won’t have the option to put it on the back burner.

Which means if a Democrat is elected president in 2020, a major piece of climate legislation will be offered in 2021. The commitments have already been made. And who knows, maybe we’ll be able to at least move closer to avoiding global catastrophe.

Read more:

Paul Waldman: The single clearest choice voters will face in 2020

Paul Waldman: The 2020 Democrats are having a real climate debate. We should take notice.

Jennifer Rubin: Maybe Democrats should run on overwhelmingly popular issues

James Downie: Sanders’s climate proposal is the best way forward

Henry Olsen: Don’t trust candidates who ignore nuclear power