I think the left wing of the two sides has embraced prudishness, rationalizing it as being feminist (female nudity => objectification => sexual violence). The left has always had a large prudish faction, so it's not really a surprise.
Eh, there are feminists that embrace sexuality too, so I don't know about all that. Personally, I think it's one of those rare situations that's not divided politically. I think there are entire subcultures in America that just don't appreciate sexuality very much.
