The Green New Deal is now a litmus test for the 2020 field

Here, though, is one thing it will do: make climate change a major issue in the 2020 Democratic presidential primary. That might not sound like a lot, but it’s truly a breakthrough, considering that global warming got short shrift in the 2016 primary and no shrift in the last general election. Four years ago, the defining fault line ran so neatly between the two parties that it often went without saying: Democrats accepted the science of man-made climate change; Republicans, almost to a man, did not. As a litmus test, it was illuminating. But it also undercut the sense of urgency among liberals. Hillary Clinton had to suffer through the occasional heckling, sure, but she knew that the climate crowd would come around by Election Day given their legitimate fears (since confirmed) about what a climate-science-denying GOP president would do.

There was already going to be far more room for climate debate this time around given the wide-open nature of the Democratic field. But the Green New Deal will now carve out space on the campaign trail for that explicit purpose; Ocasio-Cortez’s ability to capture the attention of liberals and conservatives alike ensures that. The proposal instantly creates the new litmus test for the left, one that will differentiate between those who accept the general reality that man is warming the planet and those who accept the specific consensus that governments need to take urgent, concrete steps to address the crisis. A candidate can pass that test without signing on to the Green New Deal, but they’ll need to get specific about what proposals aren’t feasible or necessary. Similarly, they’re free to get their hands dirty and weigh in on some of the thorny questions the Green New Deal framework doesn’t try to answer, including how best to pay for it. But platitudes will no longer suffice.