I still don't fully understand why indigenous comics have become a marginal phenomenon within the US.
He actually answers that question (though he seems to be unconscious of it) in this post, which reminds me of a couple of comics panels I was on at this year's CONvergence, and one from last year.
Continued below the cut...
The problem is partially that the big two, DC and Marvel, aren't really mass media any more. They're publishing for the benefit of collectors, the kind of people satirized by The Simpsons with their character The Comic Book Guy. They keep messing with the old superheroes, making them modern and relevant and "interesting", retconning and rebooting all over the place without stopping to think what they're actually doing to the iconic value of those characters. Meanwhile, just about every non-superhero comic line at DC and Marvel has been killed off. You can still find the Archie comics in paperback format at the grocery store, but I think those are mostly reprints...but that's about it. There are no other continuing series that don't feature superheroes.
Not only do they futz around with the characters, but the price of comic books is just nuts these days. For $3.50, you get about twenty pages of 4-color story once a month, and that's all, folks. In contrast, you can pick up a 200-page copy of Ai Yori Aoshi from Tokyopop for $10. Granted, the interior art is black and white, but it's outstanding art, and the color cover is pretty fabulous as well. Granted, you see a lot of short-run/special-edition comic books reprinted as graphic novels, but odds are of they didn't sell well as individual books then you won't see them as graphic novels.
Returning to the topic of the first paragraph, I think comics have also gone astray from their roots in that they have become (like so many other parts of pop culture) Hollywoodized and overly political. WTF have things come to when the current Secretary of Defense can be depicted as the Red Skull in the pages of Iron Man? Some folks no doubt find this appealing, but most of them probably don't buy a lot of comics to start with.The original target market for comics (teenage boys) has become increasingly conservative politically these days and isn't likely to be too amused by such plot devices, to say nothing of the notion of an America secretly controlled by Lex Luthor
So it is that manga and webcomics have become increasingly popular to American boys and girls while traditional comic books fade into a fringe medium. Manga and webcomics talk about ordinary people having extraordinary things happening to them, and even the robots turn out to be more human than machine. Kids like that; they feel they have more in common with Mahoro Ando than with Iron Man these days, and who can blame them?