How a Teamster Leader’s Flirtations With Trump Have Divided the Union

Sean O’Brien, the president of the International Brotherhood of Teamsters, has framed his decision to speak at the Republican National Convention next week as a savvy maneuver to keep the union’s doors open to whoever prevails in November’s presidential election.

But his open flirtation with former President Donald J. Trump has divided the union’s leadership, rankled some of its 1.3 million members and set up a showdown over the Teamsters’ eventual endorsement that has undermined President Biden’s standing with organized labor just when he needs it the most.

“We will not allow the working-class labor movement to be destroyed by a scab masquerading as a pro-union advocate after doing everything in his power to destroy the very fabric of unions,” James Curbeam, the national chairman of the Teamsters National Black Caucus, wrote in a blistering letter to Teamsters members after Mr. O’Brien announced a meeting with Mr. Trump earlier this year.

On Monday, a Teamsters spokeswoman, Kara Deniz, defended what she framed as bipartisan overtures and shot back at Mr. O’Brien’s critics.

“The Teamsters have never been afraid of democracy, but self-interested ideologues — on the left and the right, within and outside the union — are terrified of democracy,” she said.