Humanity must declare war against climate change, Bernie Sanders said Tuesday, treating it like a military threat that demands full engagement.

“We must look at climate change as if it were a devastating military attack against the United States and the entire planet. And we must respond accordingly,” Mr. Sanders said in a Tweet.

We must look at climate change as if it were a devastating military attack against the United States and the entire planet. And we must respond accordingly. — Bernie Sanders (@SenSanders) January 1, 2019

A true believer in manmade climate change, Mr. Sander’s expressed his “delight” last July at the resignation of EPA director Scott Pruitt.

What we have got to do now, Sanders said, “is to see if we can get a handful of Republican senators to understand that climate change is real, that environmental protection is enormously important for this country, and get them on board to demand that Trump appoint an EPA administrator who represents the American people and not just the fossil fuel industry.”

Sanders said that Pruitt’s replacement at the EPA, Andrew Wheeler, “should be vigorously opposed.”

“Not every Republican agrees with Trump or Pruitt that climate change is a hoax,” he said. “There are many Republicans who understand that it is real, that it is an enormously serious issue.”

No stranger to hyperbole and grandiloquence, Sanders told Sarah Silverman last September that America “starves little children” and bombs “houses and buses of children.”

Mr. Sanders said in November that he is thinking of running for president again in 2020, saying he is “looking at it” and that will do so if he concludes he is the strongest candidate to defeat President Donald Trump.

“I will make that decision at the appropriate time,” Sanders said.

“We’ve got some great people out there who are thinking of running,” he said. “They are my friends. And I’ve got to make that decision that, based on my background, based on my past, based on my ideas that, in fact, I am the candidate that can defeat Trump.”

Mr. Sanders has embraced the title of “socialist,” putting himself to the left even of many democrats. On first winning election to the House of Representatives in 1990, he famously said, “I am a socialist and everyone knows that.”

In a 2016 interview, Sanders said he thinks that Pope Francis is a socialist who believes, like him, that wealth is not “an end in itself.”

“To be a socialist,” said Sanders, “in the sense of what the Pope is talking about, what I’m talking about, is to say that we have got to do our best and live our lives in a way that alleviates human suffering, that does not accelerate the disparities of income and wealth.”

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