After three and a half years of rebuilding his reputation, Larry Summers has officially recovered from his ouster as president of Harvard: Barack Obama will name him the president of the National Economic Council, coordinator of the White House’s economic policy.

Welcome to Lawrence Summers’ third act.

With his new White House post, Summers looks to be in a position of immense power. Obama has announced plans for a massive spending and jobs initiative, and Summers would presumably oversee that effort.

In the Democrats’ weekly radio address, Mr. Obama said he would direct his economic team to craft a two-year stimulus plan with the goal of saving or creating 2.5 million jobs. He said it would be “a plan big enough to meet the challenges we face.

…Mr. Summers, who served as a campaign adviser to Mr. Obama, has advocated for a forceful stimulus plan in recent newspaper columns, saying the federal government should be doing more, not less, in areas like health care, energy, education and tax relief. Mr. Obama seemed to echo those thoughts in his radio address.

It is a remarkable turn of events for Summers, who had fallen about as far as one could fall when in 2006 he resigned the position of Harvard president after just five years in the job. He has rebuilt his image by focusing on the area of his expertise, economics. Perhaps the most important element of Summers’ rehabilitation was the fact that Harvard alum Chrystia Freeland—no dummy, she—offered Summers a column in the Financial Times. Summers also appeared in friendly forums on television, helped start a thinktank, invested in an earnest (but, IMHO, longshot) website, and occasionally appeared at Harvard, though his $400,000-plus salary does not require it.

Summers also downplayed his connection with the hedge fund D.E. Shaw, which was a blatant attempt to cash in on the hedge fund frenzy—just, as it turned out, a little late in the game.

There’s a part of me that admires and congratulates Summers for his comeback. It’s a very American thing, a comeback, and I think one should always offer people the chance to recover from a fall. We don’t always like it—there are some people who should go away and never come back—but it is one of the great things about America. And the process can’t have been easy for Summers, who certainly does have a lot to offer in the economic realm. It’s impossible not to appreciate his work ethic.

At the same time, Summers is a complicated man, emotionally and psychologically, and one hopes he learns the right lesson from this. It would be unfortunate if he interpreted his restoration as a vindication of his style of governance at Harvard—the imperiousness, the arrogance, the boorish behavior. (Not terms that he would use, of course.)

Summers’ comeback is an affirmation of his many talents, but it is not a rejection of the many concerns that the Harvard faculty and administration had about him. If Summers can, on the deepest level, accept that those concerns were legitimate, and translate the lessons learned from such acceptance into personal and professional maturity, then he will be an outstanding public servant indeed.