WATCH: Andrew Sullivan loses it over Malcolm Nance in MSNBC meltdown

Conservative commentator Andrew Sullivan went on an unhinged rant on MSNBC's "Hardball" with Chris Matthews on Tuesday.

The outburst occurred after MSNBC political analyst Zerlina Maxwell mentioned the 2018 book The Plot to Destroy Democracy: How Putin and His Spies Are Undermining America and Dismantling the West by Malcolm Nance.

"Jesus Lord, you're recommending that guy?" Sullivan interrupted.

"Yes, I am," Maxwell calmly replied.

"He's a complete fantasist," Sullivan charged.

"Who's this?" Matthews asked.

"This guy Malcolm Nance," Sullivan answered. "He spreads so many conspiracy theories and nonsense and you're citing him?"

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