It’s taken as read that other countries (at least, Western ones) will embrace stories set in the US, and media created in the US. Much of our cultural intake is TV, movies, and music from American sources. But the reverse is much less the case. Sure, there are, for example, breakthrough British bands in the US, but even taking into account the relative population sizes, far fewer have historically made that leap. That’s even more evident regarding television. Our networks are saturated with US fare. The reverse just isn’t true. And it’s especially sad when you see great indie fare like Attack the Block and Shaun of the Dead being ignored in the US because of “difficult accents” or, more often, just because the films are set somewhere other than the USA.
It's like selling Hollywood made Kaiju films to the Japanese – hard but can be done with a modicum of success.
Dredd has somewhat found a level in the US that is more in-line with how it's received globally: does ok as a niche at home –still not exactly mainstream– and enjoys a simlar niche following everywhere else on the planet. It's a little better now and both JD films still made more money at the box-office in the US, then did a lot better in retail, than anywhere else, and the comics have consistently averaged 4000-5000 monthly sales. Unless some new strategy in another format breaks that ceiling it will likely remain in place.
Selling Dredd to Americans is something I don't think can be reduced to them not getting or liking it. I think plenty of modern Americans have no aversion to critiques or sardonic takes on an 'America' that's failing/failed but it's easier for them to accept when it's done by their own talent and through familiar touchstones – that probably applies in every country and is as much about cutural recognition and familiarity as the quality of the content itself.
Selling Dredd, Attack the Block and Shaun of the Dead worldwide seems to be just as tough as trying to sell it in the US. American Superheroes (and Manga) have been the best-selling comics worldwide for decades so it's no surprise they're accepted so readily by the world in multiple formats/platforms as well as at home.