Leftist scholar Noam Chomsky has a message for voters who refused to cast their ballots for Hillary Clinton to prevent Donald Trump from winning the White House: You made a “bad mistake.”

On both moral and practical levels, Chomsky told Al Jazeera‘s Medhi Hasan, the choice was clear.

“Do you vote against the greater evil if you don’t happen to like the other candidate?” asked Chomsky, who spoke out during the election against Trump’s candidacy—and in fact predicted his rise six years ago. “The answer to that is yes.”

With an argument similar to the one made by political scientist Adolph Reed prior to the election, Chomsky insists that voters did not have to ignore Clinton’s serious shortcomings in order to recognize Trump as the much more serious threat.

“I didn’t like Clinton at all, but her positions are much better than Trump’s on every issue I can think of,” the professor emeritus of linguistics at Massachusetts Institute of Technology (MIT) told Hasan. Chomsky supported Bernie Sanders during the Democratic presidential primary.

Watch:

Noam Chomsky tells me on @ajupfront that leftists who didn’t vote for Clinton to block Trump made a “bad mistake”:pic.twitter.com/L3fr4zoKsI — Mehdi Hasan (@mehdirhasan) November 24, 2016

Chomsky also objected to philosopher Slavoj Zizek’s post-election argument that Trump’s victory would “shake up” status quo. “Terrible point,” Chomsky said of Zizek’s take. “It was the same point that people like him said about Hitler in the early 30s.”

“He’ll ‘shake up the system’ in bad ways,” Chomsky said of the president-elect. “What it means is now the left—if Clinton had won, she had some progressive programs. The left could have been organized, to keeping her feet to the fire. What it will be doing now is trying to protect rights…gains that have been achieved, from being destroyed. That’s completely regressive.”

Indeed, Chomsky further warned in the aftermath of the election: “The outcome placed total control of the government—executive, Congress, the Supreme Court—in the hands of the Republican Party, which has become the most dangerous organization in world history.”

The GOP “is dedicated to racing as rapidly as possible to destruction of organized human life. There is no historical precedent for such a stand.”