I hate Wario's biting move the most.

Mario, Luigi, Wario, Waluigi all looks like Spanish Latino, aren't they?

Play the game earthbound for the snes. That is suppose to be an american town. SO I guess that is how they view americans.

Characters like Mario are made to stereotype an Italian. Come on...the accent, the love for Italian foods...its unmistakable.

I also hate wario.

That is why I just love that screwattack put him on their top ten douchebags of gaming list.

I don't think that is how the japanese view americans though.

probably not its just a character

I think he was just styled as the "anti-Mario." He was invented by the team, led by Yokoi, which did the Mario and Wario games for Game Boy, and I think they just wanted an identity different from Miyamoto and his home console Mario team.

Japan actually has a very positive view of Americans, which is strongly shown and suggested in Anime.

It's not really Japanese who show too many negative views towards us, although they do like everyone else from time to time, it's more Europeans that show negative views to Americans. And of course other anywhere else, but not Japan too much haha.

 Yes of course.  He's the ant-Mario which is shown in many ways such as his dress and behavior.  Of course the most obvious one is name choice.  Wario is his name cause a "W" is the flip of an "M" or the opposite.  Making him the opposite of Mario.  But that's all Wario is, the opposite of Mario.  Kinda like how Dark Link is to Link and Dark Samus is to Samus.