The Cost of Censoring Political Opinions

I can see how censoring somebody's political opinions might actually be dangerous to good government. I don't like living in a society where there's lots of pornography or people very interested in that, but got to live with it. But on the whole, I'm relatively comfortable with the idea that technical information about the production of armaments is something that is permissible to regulate. The main worry seems to be at the margin whether some kinds of information about military armaments become important political things you need to know about.