 For all the people who'd rethought their feelings about Donald Trump at the Republican National Convention in Milwaukee this week, there was one guest for whom the rethink has been especially dramatic. And that's Sean O'Brien, a lifelong Democrat from Massachusetts. Sean O'Brien is the head of the Teamsters Union. 1.3 million truck drivers, rail, air, all transportation, delivery workers, lots of jobs. They endorsed Biden in 2020. And Sean O'Brien was at the RNC to give a speech. Big speech, actually. The keynote speech on the first night of the convention.