When Donald Trump on Monday chose Senator J.D. Vance of Ohio as his running mate it excited populists — and unnerved some business elites. Later that evening, the president of the Teamsters, Sean O’Brien, gave a prime-time speech at the Republican National Convention. “Over the last 40 years, the Republican Party has rarely pursued strong relationships with organized labor,” O’Brien said. “There are some in the party who stand in active opposition to labor unions — this too must change,” he added, to huge applause. There’s something happening here — a real shift in the Republican Party. But at the same time, its official platform, and the conservative policy document Project 2025, is littered with the usual proposals for tax cuts, deregulation and corporate giveaways. So is this ideological battle substantive or superficial? Oren Cass served as Mitt Romney’s domestic policy director in the 2012 presidential race. But since then, Cass has had an evolution; he founded the conservative economic think tank American Compass, which has been associated with J.D. Vance and other populist-leaning Republicans, like Josh Hawley, Marco Rubio and Tom Cotton. In this conversation, we discuss what economic populism means to him, what it looks like in policy, and how powerful this faction really is in the Republican Party.