You could not be more wrong. So tell me, if anime is only made in Japan, how did Tom and Jerry make the list of the top 100 anime in a poll taken by Japanese people? Also, you're just generalising everything, there is no 'manga style', maybe from the few titles you've seen, but there's no way something like Monster would be thought of as manga style, same with other titles like Claymore or D. Greyman. So yes, manga and Doujinshi can made by non Japanese people and out of Japan.
Manga ARE comics. If they're not then you have a lot of misguided Japanese who don't know they're wrong when they call X-Men, Superman, Green Lantern, etc, manga. Manga is the Japanese word for comic, just like anime is the short word for the animation. Elitist 'otaku' think of the words as nothing more than them meaning Japanese comics and cartoons. As much as I like bursting their petty little bubble, it does get old.