Dimon, speaking at a Business Roundtable event on Wednesday, said giving the government control of companies allows them to be used for political purposes, leading to deterioration. He said it would be a “huge mistake” for the U.S. to go down that path.

The Vermont lawmaker, a presidential 2020 contender who calls himself a socialist, shot back.

“I didn’t hear Jamie Dimon criticizing socialism when Wall Street begged for the largest federal bailout in American history—some $700 billion from the Treasury and even more from the Fed,” he wrote on Twitter.

Dimon has previously said JPMorgan, which expanded during the crisis by acquiring collapsing rivals, didn’t need a bailout to survive. In 2012, he told the Senate his firm temporarily accepted money from a Treasury Department program because “we were asked to” so weaker rivals could tap it without being singled out.

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