Social Democratic America by Lane Kenworthy Oxford University Press, 238 pp., $27.95

Barack Obama’s fifth State of the Union address received the usual praise from Democrats and many cable news commentators, but the fact is the occasion was rather grim, and his approach in some ways frustrating. With all his talk of raising the minimum wage and other executive actions that would circumvent Congress, he implicitly admitted that progress on Capitol Hill is now all but impossible. At the same time, he couldn’t quite bring himself to invite direct confrontation with the Republicans, who control the House and will continue to block most of his programs. The general verdict on MSNBC was that he was successfully positioning himself above the fray. But is that really possible in today’s Washington? The city seems all fray, all the time.

When it came to policy, the speech highlighted the set of economic concerns that has risen to the forefront of Democratic politics these last couple of years: “Obama Vows to Act Alone on the Economy,” as The New York Times summarized matters the following day. The president spoke of unemployment insurance and similar issues related to the economic struggles of the middle class, emphasizing measures that could be carried out by executive orders. He did not, as many liberals had hoped, speak at length about inequality. Apparently he and his advisers decided that was a bit of a downer for a State of the Union address and chose instead to stress inequality’s sunnier flip side of expanding opportunity. But the point was made, perhaps as much by what wasn’t in the speech—no pleas for reducing the deficit and cutting entitlements, to name two inside-the-Beltway priorities that liberals loathe and that Obama had previously suggested he favored or would at least consider.

There exists these days, among Washington policy intellectuals and advocates who tilt toward the left end of the accepted political spectrum, a certain measured optimism. It’s not about Obama, or any feeling that he might somehow, with his sagging poll numbers, be able to persuade congressional Republicans to fund, say, an infrastructure investment bank. Confidence is appropriately near zero on matters like that. Rather, it’s about the widely held perception that the Democratic Party, after years of, in the argot, “moving to the right,” is finally soft-shoeing its way leftward, away from economic centrism and toward a populism that the party as a whole has not embraced for years or even decades.

This change has occurred not by way of sweeping dramatic gestures on Obama’s or anyone’s part, but subtly and incrementally. Obama’s contribution to the shift has been mostly rhetorical, but of course presidential rhetoric matters, so when he started addressing such issues as income inequality more directly in his speeches, many observers read into it certain clear policy implications.

“This growing inequality is not just morally wrong, it’s bad economics. Because when middle-class families have less to spend, guess what, businesses have fewer consumers,” he…