As liberals grapple with rising populism and authoritarianism, Traub turns to history and theory to reclaim liberalism’s principles. His book mounts one of the best efforts of this kind yet, tracing liberalism’s core ideas from the age of democratic revolutions to the grand ideological struggles of the twentieth century to the convulsions of the current vexed moment. Traub shows that liberalism is an amalgam of often conflicting ideas: classical republican principles, Lockean individualism, the commitment to popular sovereignty, and evolving notions of rights and progressive social ideals. Various settings and figures populate the narrative, but Traub sees John Stuart Mill as the pivotal thinker linking the classical and modern strains of liberalism. Mill insisted that political institutions had to manage the tradeoffs between liberty and equality and foster the social conditions for individuals to flourish. In the United States, the reformist ideas of Theodore Roosevelt, Woodrow Wilson, and other progressives in the early twentieth century brought these impulses into the industrial age, but only through President Franklin Roosevelt and the New Deal did modern liberalism find a way to bridge a Jeffersonian appeal to citizenship and a Hamiltonian commitment to an activist state. Traub argues that liberalism lost its way in the 1990s, aligning itself with globalization and losing its deeper commitment to a progressive vision of nationalism and the common man.