My old comrade David Aaronovitch spent seven years writing Voodoo Histories, his excellent dissection of conspiracy theories. (You can buy it here and read a piece I wrote about it for Standpoint here). In the States, a Moon landing conspiracist went up to Buzz Aldrin and called him a “coward” and a “liar” for refusing to admit that Apollo 11 was a fraud. I don’t know if Aldrin wondered for a moment if he should spend seven years researching and  debunking conspiracy theories. If he did he decided against it, and smacked the conspiracist in the kisser instead. Full story here