Techically Danbooru is *not* a porn website. It's an anime art website that happens to allow porn. I don't think we've ever had any drive to censor comments though.
Geez, I'll explain for you guys. First and last panels are military training, you have to aim accurately even when you're totally fucked up. Second panel is a concentration training, you can lose your boner even with a gun pointed to your face. Third panel is a trick, making your enemy lose concentration in the middle of the fight.