When Rick Santorum chided President Obama for encouraging all Americans to go to college, he received widespread criticism, but it may still have been good politics. According to new survey data, the value of college has been politicized and it is an issue on which liberals and conservatives are worlds apart.

Last week, in a YouGov/Polimetrix survey, I asked a representative sample of Americans about the value of a college education and what they think college does for those that attend.

First the good news: a majority of all types: Republicans and Democrats, liberals and conservatives say that college is, at least, somewhat important to financial success. Unfortunately, the agreement ends there.

Respondents were asked to think about the importance of college to financial success. While similar numbers of liberals and conservatives indicated that college is "somewhat important", liberals were 20 percentage points more likely than conservatives to say that college is "very important". In fact, only a little more than one quarter of self-identified conservatives and a similar proportion of self-identified Republicans agree that college is "very important" to financial success.

Similarly, while a majority of both liberals and conservatives believe that after four years of college a person is usually at least "somewhat more educated", liberals are more than twice as likely as conservatives to say that a person will be "much more educated" after college (39% to 17%).

What underlies these differences in beliefs about the value of higher education? It could very well be a matter of political ideology: I also asked what usually happens to a person's political ideology after four years of college -- only 4% of liberals thought that a person becomes "much more liberal", while 34% of conservatives think college has this liberalizing effect.

Who do conservatives think is responsible for this liberal indoctrination and lack of effective education? I don't know for sure, but the ideological divide in opinions about college professor is suggestive. When asked how favorable they find professors, 69% of liberals said "somewhat" or "very favorable", while only 21% of conservatives had favorable opinions about people in my profession.

The importance of ideology to the value that the typical American attaches to higher education is tremendous. When I construct a statistical model that accounts for a person's income, gender, education, race, where they live, and whether or not they are the parent of a minor child -- conservatism is the single most powerful predictor of whether a person thinks a college education is important to financial success, the effect a person thinks college has on political ideology, and their opinion of college professors. In fact, political ideology is more strongly associated with a person's views on college professors than it is their views on PresidentObama! When compared to liberals, the amount that conservatives discount the value of college is about the same amount that persons with high school diplomas discount college when compared with college graduates.

So what is this cause of this ideological divide about the importance of college? Well, first it is important to note that if conservatives suspect that most college professors are liberals, they are correct. Additionally, there is reasonable evidence that students become more liberal during college, although whether it is college itself that causes this is unclear. Of course, a college education is also undoubtedly correlated with financial success.

However, much of the divide in opinion surely has to do with the messages sent by political elites. Regular voters are unlikely to think that the value of college is a political matter until politicians like Rick Santorum tell them so. With any political question, the average person does not spend their time thinking about whether seemingly non-political matters are consistent with their political ideology. This is why, for example, opinions about matters like healthcare reform are greatly affected by the association of the issue with Obama. It is this association that allows Democrats to know that they should support Obamacare and allows Republicans to know that they should oppose it. For many issues, the matter may simply be too complex or unimportant (or both) for the average voter to spend precious time worrying about, so the messages sent by political elites helps them to determine where they should stand. And, of course, for other issues, it is simply not clear why it should be politicized at all.

The value of college is a good example of such an issue -- there is no good reason why college educations should be favored by liberals and not conservatives. But, when given a signal by a politician with whom they identify and trust -- the public brings their opinion on issues into line with their ideology. It is a little worrisome if this alignment between issues and ideology causes people to devalue education -- but my guess is that most people, politics and the opinions of Santorum not withstanding, want a college education for their children, even if it means that they will have to associate with people as unpleasant as college professors.﻿