We are witnessing one of the more rapid turnabouts in recent American political history. President Obama’s popularity has plummeted to 50 percent and lower in some polls, while the public expresses even less confidence in the Democratic-led Congress and the direction of the country at large. Yet, just eight months ago, liberals were talking in Rovian style about a new generation to come of progressive politics — and the end of both the Republican party and the legacy of Reaganism itself. Barack Obama was to be the new FDR and his radical agenda an even better New Deal. What happened,...