Director and actor Rob Reiner warned Monday on MSNBC’s “All In” that if the Democratic presidential nominee does not beat President Donald Trump in 2020, America will lose our Democracy to Trump’s authoritarianism.

Reiner also said the earth would become uninhabitable due to inaction on global warming.

On his support for former Vice President Joe Biden, Reiner said, “I was a Joe Biden supporter for a year. And my position always was if Joe Biden I knew there was going to be a lot of candidates. I knew who all, you know, Elizabeth Warren, I knew Bernie was coming back, Cory Booker and all that. I said, if he can somehow make it through the Democratic primary process, he’s by far the best candidate to beat Donald Trump — first of all, to unite the party, to beat Donald Trump, to hold onto the Congress, to get the Senate, and to be able to govern and to be able to bring back the world to America’s side.”

Discussing Trump’s 2016 victory, Reiner said, “We know what he is now. We might not have known then. We know what he is now. He’s a liar. He’s self-involved. He doesn’t understand how public policy works.”

He continued, “This is very important. We are looking at two existential crises; democracy and the world, the earth. If we don’t take this presidency away, we’re going to lose democracy, and we’re going to lose our ability to live on the earth. And I want to just remind people, Bush/Gore. And people who are friends of mine said ‘I’m going to vote for Ralph Nader, there’s no difference between the candidates.’ Please, that’s a 20-year start on climate change, and we don’t go into Iraq. I’m just saying. You have to unify behind whoever.”

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