Since the 1960s, the Democratic Party has transformed. From a party rooted since the New Deal era in both “developmental liberalism” and a version of social democratic class politics, it has grown into a broad but precarious canopy beneath which shelters a fractious mix of political interests and formations, from finance-friendly fiscal policy to redistributionism, and a fragile barbell-shaped electoral coalition. The 2024 U.S. elections underscored the difficulty that American liberalism...