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As for younger folks, no surprise that there aren't many conservatives, but also some surprise that they aren't higher numbers of liberals. Younger folks tend to have less real-world experience and more idealistic views and they also know that the road to tenure is probably not improved by being identified as a strong conservative.
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<p>Actually, it doesn't surprise me at all that a strong majority of young academics self-identify as "moderates." The statement that "the road to tenure is probably not improved by being identified as a strong conservative" is just about half-right; the full truth is, the road to tenure is not improved by rocking the boat politically, either on the left or on the right. The safest path is to keep your head down and not make any enemies, and generally that means having your politics take a back seat so as not to generate controversy. In short, tack "moderate" until you get tenure.</p>
<p>As for the relatively higher levels of conservatism among the 65+ cohort, it may be partly the aging process---though the less charitable version of that is that older people are by and large more resistant to and uncomfortable with change. But I also suspect it's partly a function of generational politics. The 65+ cohort includes everyone born before 1943: pre-boomers, who went to college and grad school in the 50s and early 60s, a generally more conservative era in American politics and cultural life. The left-most cohort is the 50-64 group, those born between 1944 and 1958: the high boomers who went to college and grad school in the late 60s and 70s. Think Vietnam era, the counterculture, the New Left, Earth Day, the rise of modern feminism. It will be interesting to see whether this group becomes more conservative as they age, or whether instead they continue to carry their generally left-ish political and cultural sensibilities with them, as they have into their 50s and 60s--long after many would have expected them to "outgrow it."</p>