The seven hours of thoughtful conversation between voters and 10 of the Democratic presidential candidates about climate change on CNN on Wednesday drove home the seriousness gap between the two major political parties. The Democrats have a deep, impressive field, full of people who take public service seriously and at least try to grapple with weighty matters.

By comparison, shortly after the town halls, Anderson Cooper reported — bemused — about the current president of the United States allegedly using a Sharpie to alter an official hurricane projection: a fundamentally unserious person whose policies are actively making climate change worse even as our window for dealing with it is closing. And the 2016 Republican primary field featured an “ideas candidate” who mocked "something called ‘volcano monitoring’" as an example of wasteful government spending. (Less than a month later, Mount Redoubt erupted less than 100 miles from Anchorage.)

This country is in a hole when it comes to science and how it affects us, and one day of substantive discussion of climate change won’t get us out of it.

But it’s a start.

It allowed the Democratic presidential candidates who participated to show that they’re serious about climate change. Now they need to show they’re serious about enacting their ambitious policies.

In the unprecedented marathon, candidate after candidate spoke passionately and thoughtfully about climate change. All clearly understand the urgent need for solutions that are sufficient to the scale of the problem; their plans are generally good and getting better by the week.

That isn’t to say their plans are all equally good, but ultimately the most important difference between the candidates on climate change — and a host of other issues — may not be about the issue itself, but about how they plan to enact the changes they propose. The difference between an A+ policy and a B+ policy is smaller than the difference between a B+ policy and a policy that never goes into effect.

Even assuming that the Democrats have majorities in the House and Senate in 2021, Republicans are certain to filibuster any significant climate legislation. And even if legislation passes Congress and is signed into law, it will surely face legal challenges from Republicans and oil companies — challenges that could be decided by a Supreme Court with a conservative majority solidified before Donald Trump became president, when Republicans refused even to vote on Barack Obama’s nominee, Merrick Garland, in 2016.

Given these hurdles, although the biggest headline of the night might have been Sen. Elizabeth Warren, D-Mass, correctly noting that Republicans and the fossil fuel industry want to distract from the industry's contribution to climate change by winding up voters about plastic straws, incandescent lightbulbs and hamburgers, the most important news of the night may have been Sen. Kamala Harris, D-Calif, saying she’d support the elimination of the filibuster in order to pass the Green New Deal.

That’s the kind of thing candidates should address going forward: Do they support the elimination of the filibuster? And, if not, how will they get 60 votes in the Senate for any legislation they support that Republicans oppose? And how will they safeguard their plans from an increasingly activist and partisan Supreme Court?

Several candidates have indicated an openness to expanding the size of the court to offset how Republicans used the filibuster to ensure the court's conservative majority; that and other potential judicial reforms — and I am working with Take Back the Court, an organization dedicated to just such reforms — should be discussed in future debates and town halls as the candidates explain how they’ll turn their plans into reality.

The urgency of the climate crisis means we don’t have time to spend years trying to pick up enough Republican votes or Republican seats to overcome every filibuster on any major climate change bill, and it means that a partisan Supreme Court blocking the implementation of any law that does pass would be a devastating setback from which the world's recovery might be impossible.

But even if advocates need to continue pressing Democratic candidates to go further, it’s worth pausing to appreciate what happened on Wednesday night.

CNN deserves credit for airing seven hours of largely substantive discussion of an existential crisis. It was the precise opposite of what cable news viewers are accustomed to, and in the best possible way. The nonsense concepts and filler words — I don’t think the word “optics” was uttered a single time, or “electability” — that tend to dominate media coverage of political campaigns was refreshingly absent, and I doubt many viewers were sitting at home wishing Wolf Blitzer would ask the candidates if they think they’re “likable” enough to win.

This is what campaigns, and coverage of politics, should be: Serious people speaking seriously about serious topics. Instead, in most other cases, interviewers and debate moderators have proven stubbornly resistant to actually asking candidates what they’ll do about climate change, which nearly every expert on the subject describes as an “existential threat.” (There hasn’t been a single question about climate change in a general election debate since 2008, and there has been a total of only three in the last five presidential elections combined.)

Given that shameful track record, there’s a danger that the news organizations that host future debates will consider the climate box checked by Wednesday’s town halls and MSNBC's two-day climate forum on Sept. 19 and 20 and go back to ignoring the issue. So the climate activists who helped make these town halls happen — particular credit goes to the Sunrise Movement — can’t let up the pressure now.

More than simply candidates discussing their plans, a debate about their climate policies and how they will enact them is essential to ensuring that the Democratic nominee has a strong climate plan. The extended health care debate between Barack Obama, Hillary Clinton and John Edwards in 2008 helped ensure that whoever ultimately became president would make the issue a priority upon taking office. The climate town halls must be a starting point, not the final word.

Regardless of whether there is ultimately a climate-focused, DNC-approved debate, climate should be a central topic at every debate. That is not only because of its importance, but because of the breadth of its importance. The damage that climate change will do to our health, our economy, our safety and our security unless we act quickly means that candidates who don’t have a plan for climate change don’t have a plan for health care, or jobs, or deficits, or national security. And whatever plan they do have for those issues isn't very good.