Opinion writer

Single-issue presidential campaigns are generally not successful, but what if the issue in question is the survival of most life on Earth?

That’s what Washington Gov. Jay Inslee (D) wants us to consider as we choose the next president, and he’s making climate change the centerpiece of the candidacy he announced on Friday. He’s also the first governor to enter the 2020 race, joining an extraordinarily diverse and growing field.

Unlike many (but not all) of his primary opponents, Inslee has a direct and emphatic answer to the question each one of them has to face: Why are you running for president? That kind of clear vision may not be enough to win, but it’s something you can’t win without.

Though Inslee has the kind of résumé one typically associates with presidential candidates — he started as a state representative, then had a lengthy term in Congress, then was elected and reelected as governor — he’s practically unknown nationally. But he can legitimately claim to have been advocating for action on climate since before some of the other candidates ever got elected to public office.

Here’s how he summed it up in an interview with Rolling Stone’s Andy Kroll:

His vision, he tells Rolling Stone, is an administration organized around the climate crisis, an entire federal government working in unison to decarbonize the economy and help save the planet. No candidate has his record on the issue, and none of them have said nearly enough about it, he says. “A lot of these candidates want to check the box,” he tells me. But one sentence in their campaign-launch events doesn’t solve this problem. “This has to be the number-one priority of the United States,” he insists. “Every agency has to be on board, and it has to take priority over everything else we do. You have to build a mandate for this during the campaign, and you have to express a willingness to spend your political capital to get this done. I think too many other candidates are going to say, ‘I’m for the Green New Deal, and now I’m done.’ That just doesn’t cut it.”

There’s something else distinctive about Inslee: He wants to get rid of the procedural and representational impediments that have hampered Democrats and progressive ideas for a long time. Of the six senators in the race, only one, Sen. Elizabeth Warren (D-Mass.), has expressed any interest in getting rid of the filibuster — and she only says that eliminating it should be “on the table."

Inslee wants to do away with it. He told David Roberts of Vox, “you can’t have antebellum rules in the Senate in the internet age. And I have the same view of the electoral college. It ought to be one person, one vote.” He also supports statehood for both the District of Columbia and Puerto Rico.

Inslee certainly has an uphill climb ahead, as someone without a national profile and, frankly, as a white guy looking to represent an increasingly diverse party. He also has to convince Democrats and a potential general electorate that climate change is indeed the most urgent problem we face.

The conventional wisdom about climate has always been that while people say they care about it, as a voting issue it's way down their list of priorities. That has made it easy to do the kind of box-checking Inslee talks about, since voters wouldn't punish a candidate who said the right things about climate but didn't demonstrate a commitment to serious action even if it entailed political risk.

But with him in the race — and obviously, with the practical realities of climate change becoming more evident on an almost daily basis — it’s going to become more difficult for the other candidates not to put out comprehensive climate plans and demonstrate that commitment.

It will also be interesting to see whether Inslee can force a debate within the party about what the next president’s most important goal should be. Is it universal health care? Fixing income inequality? Or climate?

Which brings us back to the question of why these people are running for president. I’ll be brutally honest: Though I think there’s a lot to like about nearly all the Democratic candidates, I couldn’t tell you why most of them are running, and it’s not because I’m not paying enough attention. Of course I know why they’re actually running — they want to be president! Which is fine; every politician you ever loved — whether your tastes run from Franklin Roosevelt to John F. Kennedy or Ronald Reagan or Barack Obama — was possessed of an almost pathological ambition. It comes with the territory.

But, so far, the only ones who have articulated a clear and coherent rationale for their candidacies are Sen. Bernie Sanders (I-Vt.) and Warren, both of whom want to attack the political and economic power of plutocrats, and now Inslee.

The others haven’t yet made their purpose as clear. Try to sum up in a sentence or two why Sens. Kamala D. Harris (D-Calif.) or Kirsten Gillibrand (D-N.Y.) thinks we should elect them president, and you won’t be able to do it. That makes it harder to imagine precisely what their presidencies would look like, which makes judging them more difficult.

One thing you can say for Inslee: He’s telling us exactly what his presidency would be about. We don’t know yet how compelling his case will be, or how primary voters will react to his insistence that climate change has to be our top priority, but the race is definitely better with him in it.

Read more:

Jay Inslee: The next president must make climate change the top priority

James Downie: The fierce urgency of climate change

John Kerry: Disband your climate denial panel, Mr. President

The Post’s View: More studies show terrible news for the climate. We should be alarmed.