President Barack Obama and Vice President Joe Biden applaud as Ashton Carter, Obama's nominee for defense secretary, speaks during the announcement, Friday, Dec. 5, 2014, in the Roosevelt Room of the White House in Washington. (AP Photo/Susan Walsh)

Harold Pollack is Helen Ross Professor at the School of Social Service Administration at the University of Chicago.

On Friday morning, President Obama nominated Ashton Carter to be the new secretary of defense.

I knew Carter long ago when I was in graduate school. I was twice his teaching assistant for a science policy class. He was a brilliant and gruff professor who attracted an eclectic mix of Harvard and MIT students. We haven’t had any particular occasion to cross paths in many years. But I am heartened to see someone of his background called forward to this position. Few are in Carter’s league for intellectual candle-power. A Rhodes Scholar with a doctorate in theoretical physics and expertise in medieval history, he checks the coveted meritocratic boxes. In some ways, he is a throwback to Richard Garwin and an earlier generation of physicists who have influenced security policy.

But these credentials are not what strike me as noteworthy in his potential appointment. Academic mandarins and business leaders have always contributed policy briefs, joined advisory committees, descended on Washington for brief periods to help craft public policies.

Carter chose to do something that few other academic stars have chosen to do. Since the early 1990s (with some breaks to return to academia), he has stuck around to actually accomplish important tasks. He did the work in multiple presidential administrations to run a monster procurement bureaucracy, to help nurture and then implement the Nunn-Lugar effort to dismantle Soviet-era nuclear weaponry, to provide better equipment to protect servicemen and women against roadside bombs.

When I look across the range of public health and social policies on which I have expertise, there are far too few people of this caliber and visibility who make such sustained contributions within government, as actual public managers. The head of the National Institute of Allergy and Infectious Diseases, Anthony Fauci comes to mind, and a few others. In too many cases, these outstanding figures are swimming against the tide.

As NYU scholar Paul Light relates in his sobering volume, A Government Ill-executed, much about Washington specifically conspires against attracting--and keeping--people with this sort of expertise. And over time, it has become correspondingly more difficult to operate and staff the federal government to accomplish important tasks.

To state the obvious, the nomination and confirmation process has become increasingly intrusive, acrimonious, and protracted. One nominee described the process as “nasty and brutish without being short.” There has been a striking increase in filibusters. Counting recent cases such as Surgeon General nominee Vivek Murthy, about as many nominees have been filibustered under President Obama as in the entire prior history of the republic before then. Procedural delays have long-plagued the process.  Carter himself was given the full treatment, bleeding financially while his nomination was delayed and put on hold in the early days of the Clinton administration.

The problems go deeper, too. Paul Light was among the first to document a disturbing trend: Even among students who receive advanced training in public policy, an increasing percentage opt for positions in the private or nonprofit sectors rather than government.

Government pay-scales lag far behind the elite business world. More to the point, the pay lags increasingly far behind what people typically earn in most technical professions. The Congressional Budget Office reports that “federal workers with a professional degree or doctorate earned about 23 percent less, on average, than their private sector counterparts.”

In my own field, the typical tenured professor might easily take a 50 percent pay cut to work in government. White House Chief of Staff Denis McDonough earns an annual salary of $172,200. (Of course most White House employees earn far less.) By comparison, a 2013 survey of full professors at my university indicates an average salary exceeding $200,000. People at the very top of their fields are earning much more.

Washington remains enticing to take a visible and important short-term gig. It’s still enticing to people who don’t mind the large pay gap, or who can burnish their subsequent consulting and lobbying credentials with a public tour of duty. The value proposition is more dubious for people outside these worlds, who ponder taking a position further down the bureaucracy where much of the important work is done--and then to stay at it when other opportunities beckon.

There are other mediocre practices, too. The Obama administration—like every one before it--awards important ambassadorships to campaign donors. Most of these donors are dedicated and public-spirited. But what message does this send to the actual experts and professional diplomats who spend decades mastering the complexities of foreign relations and the workings of other societies?

This is a terrible problem, particularly as the world becomes more complex and interconnected, as science and technology become more central in a global world, as the inevitable relative decline of American power creates new challenges and opportunities that require different forms of expertise.

Assuming that he is confirmed, Carter will have much to contend with in a tough outside world and a tough domestic political environment. I have no idea whether he will succeed. I have no idea whether I will even agree with him. I do know that he has earned the opportunity to try.