ASSOCIATED PRESS Sen. Bernie Sanders (I-Vt.) delivered a response to Trump's border wall speech shortly after Democratic leaders offered their own rebuke of the president's address.

Sen. Bernie Sanders (I-Vt.) called climate change “the biggest crisis of all” in a fiery rebuke of President Donald Trump’s televised address Tuesday night meant to drum up support for funding a U.S.-Mexico border wall to reopen the federal government.

Speaking shortly after Trump’s prime-time Oval Office speech, Sanders listed the 30 million Americans without health insurance, the millions of senior citizens in “desperate poverty” and the 40 million young Americans “trying to deal with outrageous debt” as issues meriting a White House declaration of a national emergency.

But the Vermont senator and likely 2020 presidential candidate said human-caused global warming should top the president’s priorities.

“The scientific community has made it very clear in telling us that climate change is real and is causing devastating harm to our country and the entire planet,” Sanders said. “They have told us in no uncertain terms that if we do not transform our energy system away from fossil fuel, our nation and our planet and the planet we will be leaving our kids and grandchildren may well become unhealthy and even uninhabitable in the not-so-distant future.”

He added: “Mr. President, we don’t need to create artificial crises, we have enough real crises.”

ASSOCIATED PRESS In this Nov. 15, 2018 photo, smoke hangs over the scorched remains of Old Town Plaza following the devastating wildfire in Paradise, California.

The clarion call capped off Sanders’ roughly nine-minute response and stood in stark contrast to the humdrum address the two top Democrats in Congress gave immediately after Trump’s speech.

In a response aired on nearly every major network, Senate Minority Leader Chuck Schumer (D-N.Y.) and House Speaker Nancy Pelosi (D-Calif.) accused the president of using “the backdrop of the Oval Office to manufacture a crisis, stoke fear, and divert attention from the turmoil in his administration” and of “holding hostage critical services for the health, safety and wellbeing of the American people.” They made no mention of climate change.

The two Democratic leaders, who were standing soberly side by side, drew mockery for appearing like two proverbial parents expressing disappointment with a misbehaving teen.

If that official Democratic response was meant to demonstrate the poise and civility that plays well with the Beltway crowd, Sanders’ seemed targeted at average American voters.

He opened with a list of people victimized by the three-week shutdown of the federal government, including “the disabled, their children and the elderly” on food stamps, small businesses and farmers owed financial assistance, and would-be homeowners or sellers awaiting the processing of mortgage applications. (He didn’t mention, however, that the Trump administration has continued processing oil and gas drilling permits, according to Bloomberg.)

Mr. President, we don’t need to create artificial crises, we have enough real crises. Sen. Bernie Sanders (I-Vt.)

Then, Sanders recalled the Senate bill to fund the government that passed unanimously on Dec. 19 and said it was “widely expected” that the next day, “the House would do the same” and “the government would remain open.”

“Unfortunately, President Trump, who started receiving criticism from an assortment of right-wing ideologues, changed his mind about the agreement,” Sanders said. He then read aloud quotes in which Trump said he is “proud to shut down the government.”

“In terms of the shutdown, President Trump has made it very clear who was responsible,” Sanders said.

In the middle of his speech, Sanders called on Senate Majority Leader Mitch McConnell (R-Ky.) directly, saying, “let’s vote to end the shutdown now in a bipartisan way.”

“It gives me no pleasure to tell you what most of you already know, and that is that President Trump lies all of the time,” Sanders said, his voice rising. “In his remarks tonight and in recent weeks regarding immigration and the wall, he continues to lie.”

Sanders stopped short of denouncing the president’s repeated statements that call the science behind global warming into question. But as he gears up for a second White House bid, the senator is making climate change a central focus of his campaign.

In December, he hosted a televised town hall talk on global warming and repeatedly tried to push the policy debate beyond whether or not climate science is real and toward “a political revolution that takes on the fossil fuel billionaires, accelerates our transition to clean energy, and finally puts people before the profits of polluters.”

In a twist, a right-wing commentator seemingly alluded to Sanders’ words on Tuesday. Erick Erickson, a vocal conservative critic of Trump, suggested on Twitter that, if GOP lawmakers cave to the president’s border demands, “it is only a matter of time before a progressive President declares climate change a national emergency and uses eminent domain to shutter coal plants, etc.”