I'm pretty sure Dredd had its central premise in place way before The Raid.
Both films are excellent though I'm not sure why The Raid necessitates a remake; it's not exactly a difficult film to follow even in a foreign language.
It doesn't. But the partially correct assumption is that mainstream American audiences will not sit through a completely subtitled film. There is an English-dubbed version on the DVD, however. And THE RAID's director is Welsh.....