It’s not even 2019 and the Democrats have already begun sniping at each other about the 2020 presidential election.

Bernie Sanders fans and Beto O’Rourke boosters have erupted into a back-and-forth as the latter try to nurture the Texas congressman’s presidential aspirations and the former push back against his moderate credentials. Ideally, this kind of intraparty debate is healthy — even if it is coming a bit early in the political cycle.

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What should make this interesting to Houstonians, Democrats and Republicans alike, is how the conversation has focused on O’Rourke’s votes in support of an oil and gas agenda.

While representing El Paso in Congress he voted to remove the ban on crude oil exports, backed a Republican bill to expedite natural gas exports, and opposed a Democratic measure to limit offshore drilling. For Texas observers, that record is a sign that O’Rourke was willing to reach across the aisle to fight for the economic interests of a state built on petroleum. However, for the left wing of the Democratic Party, those votes are proof that O’Rourke is a sellout to the fossil fuel industry.

As David Sirota framed it in The Guardian: “[D]espite the imminent climate catastrophe facing our planet, O’Rourke has often taken the side of carbon polluters.”

So which side is right? Here’s the tough answer: They both are.

It is the fundamental responsibility of any good local representative to support the immediate material interests of his or her constituents. In Texas, that means preserving oil and gas jobs. There’s a reason why Houston’s newly elected U.S. Rep. Lizzie Fletcher, a Democrat, took a stand in support of offshore drilling.

On the other hand, humanity has 12 years before climate change begins inflicting unprecedented and irreversible harm, according to the most recent report from the U.N. Intergovernmental Panel on Climate Change. Only massive changes to public policy and the energy industry will stem carbon emissions enough to make a difference — the kinds of changes that could turn Houston into a 21st century Rust Belt city.

If Democrats can’t find a way to speak to the economic realities in Texas, expect the blue dots growing across the Lone Star State to start shrinking and possibly the House majority along with it.

On the other hand, if fans of fossil fuels can’t find an effective way to address climate change, Texas will have to start dealing with problems even more destructive than an oil bust.

Politicians across the spectrum should face this moment as an opportunity to organize their best ideas and smartest policies and present them to the American people. What would an effective carbon tax look like? What would a Green New Deal mean for Houston’s refinery workers?

Whether it’s Beto or Bernie, these are among the issues that need to dominate the conversation about 2020.