re: Risk. That game boils down to cashing in the extra armies cards at the right time... in order to consume other players to get their cards... with which to cash in on even more armies... ad finatum. The game is won by the by the player best trying to emulate Sherman's March to the Sea. A sometimes fun but ultimately repetitive experience.
re: Axis & Allies. I remember this game being much more entertaining in my youth. Also a game of consistent repetition where pretty much any successful opening revolves around a German blitz on Russia towards Moscow, and a Japanese recreation of Pearl Harbor. Accomplishing these feats pretty much ensures an Axis win, and failure means an Axis loss. I would credit Axis & Allies, however, as perhaps the creative force behind Attack!, a far superior game. Or Supremacy, a game I'm not sure I ever want to talk about again.
re: War, the card game. A kind of boredom packed into a deck of cards you never thought possible. I would sooner play 52-card Pickup, and at least have the satisfaction of having accomplished something.
re: Diplomacy. A game that separates the good from the lucky. No random elements make it a wonderful exercise in tactics and social skills that few, if any, board games can match. It's biggest hang up is that it required 7 like-minded people with similar availability. However, sites like this one eliminate that worry. So three cheers for the internet, which deliver to me Diplomacy and porn (two of my favorite food groups)!