This has become a hot topic, prompted by, among other things, the launch in November of the Washington Center for Equitable Growth, President Obama’s inequality and mobility speech in early December, and Ezra Klein’s recent comments. My current thinking is here.

That’s the title of my essay in the January-February 2014 issue of Foreign Affairs. You can read it at foreignaffairs.com. It’s free; you simply have to register. Here’s the opening:

Since March 2010, when U.S. President Barack Obama signed the Affordable Care Act into law, the ACA has been at the center of American politics. Tea Party activists and their allies in the Republican Party have tried to stymie the law at nearly every turn. The Republican-controlled House of Representatives has voted more than 40 times in favor of repealing or defunding it, and last October the House allowed a partial shutdown of the federal government in an attempt to block or delay the law. The controversy surrounding the ACA shows no sign of ending anytime soon.

Obamacare, as the law is commonly known, is the most significant reform of the U.S. health-care system in half a century. It aims to increase the share of Americans who have health insurance, improve the quality of health insurance plans, and slow the growth of health-care spending. But the fight over the law is about more than just health-care policy, and the bitterness of the conflict is driven by more than just partisan polarization. Obamacare has become the central battleground in an ongoing war between liberals and conservatives over the size and scope of the U.S. government, a fight whose origins stretch back to the Great Depression and the New Deal….

The ACA represents another step on a long, slow, but steady journey away from the classical liberal capitalist state and toward a peculiarly American version of social democracy. Unlike in, say, northern Europe, where social democracy has been enacted deliberately and comprehensively over the years by ideologically self-aware political movements, in the United States, a more modest and patchy social safety net has been pieced together by pragmatic politicians and technocrats tackling individual problems. Powerful forces will continue to fight those efforts, and the resulting social insurance policies will emerge more gradually and be less universal, less efficient, and less effective than they would otherwise have been. But the opponents are fighting a losing battle and can only slow down and distort the final outcome rather than stop it. Thanks to a combination of popular demand, technocratic supply, and gradually increasing national wealth, social democracy is the future of the United States.

That’s the title of my new book. It’s available from Oxford University Press, amazon (the kindle version is just $10 and looks nice), and other booksellers.

You can read the introductory chapter for free. Jared Bernstein, Tyler Cowen, Jacob Hacker, and Reihan Salam were kind enough to write blurbs.