Whatever Rick Santorum's fate in the New Hampshire primary today, his near win in the Iowa caucuses inspired columnists Michael Gerson and David Brooks to burnish the candidate's image not only as champion of the family and conservative Christianity but as a political thinker. Santorum, they argued, is shaped by Catholic social teachings and in particular by the Catholic principle of subsidiarity.

Subsidiarity is a term used by John Paul II and a string of Catholic thinkers--including G. K. Chesterton--to argue that some activities belong to subsidiary or local agencies rather than to a dominant central organization. Subsidiarity means that the state should not try to take over functions that are properly the concern of the family, school, church, union, corporation or local government.

Subsidiarity is a fertile idea, though more suggestive than prescriptive. It's hard to pin down what subsidiarity actually means, apart from some extreme cases. (Yes, we can agree that the federal government shouldn't decide what families eat for breakfast or when neighborhoods hold their block parties or who should teach seventh grade.)

Most users of the term tend to forget one crucial element of the subsidiarity principle: larger organizations are always obligated to step in to coordinate or supplement the activities of smaller organizations when such action is necessary to protect human rights and serve the common good. John Paul II made this point explicitly when invoking subsidiarity in his 1991 encyclical Centesimus Annus:

The state has the right to intervene when particular monopolies create delays or obstacles to development. In addition to the tasks of harmonizing and guiding development [the state must also act] when social sectors or business systems are too weak or are just getting under way, and are not equal to the task at hand.

In other words, the subsidiarity principle is far from a slam-dunk argument against state intervention in schools, corporations or families. It is, instead, an argument for appropriate state intervention. So what's appropriate?

It can be argued regarding health care, for example, that private companies have proven unequal to the task of providing citizens with adequate health care and therefore it is necessary--precisely on the basis of subsidiarity--to create a state-sponsored national health insurance program. That's probably not the version of subsidiarity Gerson and Brooks have in mind.

Subsidiarity has "liberal" implications in other areas, too. For example, subsidiarity suggests that people working in an office or factory are best equipped to make most decisions about their workplace. Subsidiarity therefore entails strong support for unions. (Think of John Paul's support for the Solidarity movement in Poland.) And subsidiarity means that neighborhoods and regions are better equipped to make decisions about what affects their local environment than are, say, the multinational oil companies that want to drill there.

I doubt Santorum has thought much about subsidiarity. And, as much as I like John Paul and Chesterton, I doubt that the principle of subsidiarity does all that much to clarify ongoing social and political arguments.