In his autobiography, Blair relates that during the buildup to the Iraq war he used to tell anti-war Labour cabinet memebers and MPs "it's worse than you think, I really believe in this". Though as that episode shows, being a true believer isn't the same thing as being honest or transparent in your justifications.

I had a brief relapse on this realisation recently, during the assault on Gaza, when it was revealed that (some) Israeli supporters on the net were coordinating and disseminating talking points using software released by PR firms (can't remember if they were offficial gov't agencies or just overenthusiastic), similar to what some AGW defenders have set up on twitter. Anyway this was briefly comforting, since I felt some of the arguments they were using were callous, and it was nice to think that they didn't really mean them, but then it was pointed out that they weren't being paid.