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Michigan Rep. Rashida Tlaib (D) might not have had an appointment on the 2020 Democratic debate stage tonight, but she and hundreds of like-minded activists were making their voices heard nevertheless. "As many as 2,000 protesters" marched on downtown Detroit on Tuesday demanding the 2020 candidates' action on Green New Deal climate change policies, HuffPost's Alexander Kaufman reports.

Activists have long demanded that the 2020 Democrats participate in a debate specific to addressing concerns about climate change; CNN has since responded with the announcement of a "climate crisis town hall" in September. Only one candidate, Washington Gov. Jay Inslee, has made climate change central to his platform.

Yet the climate is a top issue for Democratic voters. In an April poll, Yale found that climate change was the third most important issue behind environmental protection and health care for "liberal Democrats," and the eighth most important issue for "moderate" and "conservative" Democrats.

The protesters on Tuesday at least made it difficult not to be noticed — they even brought a band:

"If you want to be the president of the richest, most power[ful], most industrialized nation on Earth, you have to accept basic moral obligations, you must come to grips with problems of corporatized industrialization and the need to correct those problems," the organizers of the protest said in notes shared with the press. "You must embrace environmental justice here at home and on a global scale."