If Democrats can win big enough in 2020, they might have a shot at passing policy to address some of the hair-raising emergencies afflicting American society — most importantly, climate change. Lefties like Alexandria Ocasio-Cortez have been developing ideas for a Green New Deal, meaning some kind of crash de-carbonization and investment program.

But due to America's anachronistic Constitution, any such legislation would have to make it over many difficult hurdles: first the committees and then the overall votes of both the House and the Senate, and then the signature of the the president. This would be hard indeed — just witness the fate of the cap-and-trade bill of 2009-10, which was extremely timid and still didn't pass.

But if you're going to start somewhere, it might as well be at the beginning — which is why Sen. Joe Manchin (D-W.V.) must be stopped from becoming the ranking Democratic member on the Senate Energy and Natural Resources Committee this January.

Here's why. Coal is by far the most significant industry in West Virginia, and dominates its politics utterly. The sitting governor is the richest person in the state, a coal billionaire who inherited his business from his father. Manchin's entire adult life has been dedicated to coal — preserving the industry, protecting it politically, and raking in his own fat profits. Before he won the special election to his Senate seat in 2010, Manchin disclosed $1,363,916 in income from the Energysystems coal company over the previous 19 months, and $417,255 on the next disclosure.

The over-reliance on coal has made West Virginia one of the sickest and poorest states in the country, in classic petro-state fashion. The political economy of digging up flammable rocks tends to be extractive, highly unequal, deadly, and corrupt. The lousy outcomes are obvious and have been for decades — but as Aaron Bady writes, when Charlotte Pritt ran for governor on a platform of moving the state beyond the dead-end of coal in 1996, Manchin campaigned hard for her Republican opponent, and Pritt lost by a whisker.

As I mentioned above, back when Democrats had huge majorities in the House and Senate, they tried and failed to pass a pathetically weak climate bill (somewhat akin to ObamaCare in its lack of ambition and convoluted design). Manchin was a ferocious opponent:

After that, he repeatedly voted against Obama's climate regulations, accused him of conducting a "war on coal," and celebrated Trump's decision to pull out of the Paris climate accords. He has a 45-percent lifetime rating from the League of Conservation Voters — occasionally voting for pro-wilderness measures but almost always against climate policy.

For the world and America, coal is still probably the biggest direct climate problem, and hence the business of mining and burning it must be extirpated. Transportation is now a larger source of emissions than electricity generation, but that is best handled with electric trains and vehicles, which require a zero-emission power generation system. (Much of that would naturally be located in former coal regions, in keeping with the economic redevelopment tradition of the original New Deal.)

As David Roberts explains, Manchin is a possible contender for leading the committee because all the senators ahead of him (Maria Cantwell, Ron Wyden, and Bernie Sanders) want to be ranking members on other committees. If Manchin skips to the front, then he becomes ranking member, and if Democrats win control of the Senate, then he would be chairman, where we would have enormous latitude to bottle up climate legislation. To stop him, either one of those three would have to step up, or the party leadership could promote someone over his head.

Now, as Emily Atkin writes, Manchin no doubt understands the challenge from the left and appears to be trying to reposition himself. He recently voted against Trump's nominee for the Federal Energy Regulatory Commission, supposedly because the guy is an open climate science denier (though he is almost certainly going to be confirmed anyway.) And sure, better to vote against him than for him. But this move is a decade late and $1,363,916 short. It's not out of the question that Manchin could have some late-in-life conversion — but it's basically impossible to imagine a worse Democrat to run a Senate energy committee. Manchin's coal baron politics are a clear and present danger to the survival of the United States and humanity writ large. You might as well put Rex Tillerson in there.

So somebody else step up to the plate — and Manchin can have a new Committee of Target Shooting and chair it in perpetuity.