(NewsNation) — Dan Rather isn’t pulling any punches on Twitter.

The former news anchor, who turns 91 at the end of the month, has taken on a fiery online persona in his later years — and yes, he writes his own tweets.

“On social media, what I’ve found is that you better write something that’s interesting or people are not going to care,” Rather told NewsNation’s Chris Cuomo on Monday. “On the other hand, you don’t want to get so caught up in writing something interesting that you don’t write something that matters.”

The veteran journalist has amassed more than 2.7 million followers and shows no signs of slowing down.

As someone who has followed the American political climate for more than 70 years, Rather called today’s landscape “a serious and dangerous moment in the American story.”

That risk has been heightened by a lack of national unity, Rather said, emphasizing that the nation is at its best when people work together.

“We tend to forget, in the rush of daily journalism … what a tremendous country this is,” Rather said.

In order to restore unity, Rather called for a return to “a more moderate approach to how we view one another.”

Rather said the stakes couldn’t be higher: “The very foundation of our constitutional republic — based on the principles of freedom and democracy — are being challenged.”

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