“Finally trashed by @realDonaldTrump. Will still reserve him a seat on the Blue Origin rocket. #sendDonaldtospace,” Amazon (AMZN) CEO Jeff Bezos tweeted last December.

This was in response to Donald Trump’s Twitter (TWTR) tirade claiming that Bezos, who also owns The Washington Post, bought the newspaper “for purposes of keeping taxes down at his no profit company, Amazon.”

At the Vanity Fair New Establishment Summit on Thursday, Bezos said at first, his instinct was to take Trump’s personal attacks in jest. But, Bezos realized that it’s crucial for him to defend US democracy, which he said is being threatened by Trump’s candidacy for president.

“I should not have taken it lightly,” he noted. “One of the things that makes our country as amazing as it is is that we are allowed to criticize and scrutinize our elected leaders. There are other countries where if you criticize your elected leader you’ll go to jail, or worse, you may disappear.”

Bezos said anyone running for president has the obligation to be as transparent as possible with the American populace.

“The appropriate thing for a presidential candidate to do is to say, ‘I’m running for the highest office in the most important country in the world. Please scrutinize me.’ That would signal great confidence. That would be the leader thing to do,” he said.

Instead, Bezos suggested, Trump’s attacks on media and his claims that the election is rigged are just creating hostility and anger, without providing a solution.

“Trying to chill the media and threaten retribution isn’t appropriate. We have freedom of speech in this country. It’s written in our Constitution. Except for our norms and behaviors, [the] Constitution is just a piece of paper,” he said. “We are not a new democracy. It is inappropriate for a presidential candidate to erode it around the edges. They should be trying to burnish it — not erode it.”

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