I see all your points, and I agree with you that House is being monumentally stupid. He has extreme control issues (see practically every episode of House) and is egotistical; he thinks he is the only one who can fix this. Also, his perspective on the world has gotten warped on this issue. College towns (as Princeton is), in my experience, tend to be rather tolerant places (unless you're Republican, hee); the danger is not lurking the way House thinks it is.

Hellspoette pointed me to Yeats' poem Two Trees: http://users.crocker.com/~lwm/twotrees.html I think it's very evocative of what is going on with House.