Have you seen the credits for alot of the Disney films, a lot of japenese names there. Lets face it. Just like the automobile industy the japanese will do it cheaper and more efficiently.
The Adult Swim cartoons on Cartoon Network have been successful–often winning their late night time slot. Sealab 2021, Home Movies, Space Ghost: Coast to Coast, The Brak Show, and of course Aqua Teen Hunger Force are all great American cartoons.