Ah yes, Uncle Jack Welker, Todd and the rest of the White Supremacist Gang. Aside from the pun on "White" (presumably deliberate, but fairly tasteless), there seems to be little reason for Jack and his gang to be a group of Nazis. Aside from the fact that, you know, Nazis are bad guys - and these guys are REALLY bad guys. The main problem with the characters is that they just have no part to play in the story until after Gus' death, and as such their "threat" seems rushed and forced - rather than steadily developed like that of the owner of Los Pollos Hermanos. Suddenly the audience is forced to accept that the biggest threat to Walt's power is a rival drug gang that hasn't actually been mentioned in the storyline up until that point, and that he has very rapidly managed to drag them under his control by paying them to kill the potential prison grasses. Yes, Jack and his troupe become very, very important during the fifth season. Walt faces his final showdown with them. And Todd, Jack's psychopathic nephew, is a pretty brilliant and truly menacing character. But the fact that the audience is effectively forced to care about a bunch of characters (who are so evil! They're Nazis, remember!) that have been dropped into a story comprised of very carefully constructed protagonists so late on is fairly poor writing. And as for their kidnapping of Jesse... It's like something from a prisoner of war film, and is clearly just a long-winded plot device designed to grant Walt some retribution in that particularly relationship.
