SOME of the smartest thinkers on problems at home and around the world are university professors, but most of them just don’t matter in today’s great debates.

The most stinging dismissal of a point is to say: “That’s academic.” In other words, to be a scholar is, often, to be irrelevant.

One reason is the anti-intellectualism in American life, the kind that led Rick Santorum to scold President Obama as “a snob” for wanting more kids to go to college, or that led congressional Republicans to denounce spending on social science research. Yet it’s not just that America has marginalized some of its sharpest minds. They have also marginalized themselves.

“All the disciplines have become more and more specialized and more and more quantitative, making them less and less accessible to the general public,” notes Anne-Marie Slaughter, a former dean of the Woodrow Wilson School at Princeton and now the president of the New America Foundation.