by spartax
Assuming it's a friendly game, I'd certainly allow a takeback in situation 1 as described in the OP. No new information has been revealed; it's easily fixed; it's cool. For that matter, I'd probably say something when he said, "I'm going to coup Brazil," like, "Do you realize that that will immediately lose you the game?"Situation 2 and 3, nope. That would take a chunk of tension out of the game.