What he's able to do is remarkable. You see other helmet teams that have all the recruiting advantages in the world, and they can't do what Saban is doing at Bama. Even a phenomenal coach in Meyer at OSU can't quite do what Saban is able to do.
I still think it's bigger than Saban though. It's institutional support with palatial facilities, it's demographic changes turning the Southeast into the most fertile recruiting bed of the country, it's being in a state [and region] where there's no professional sports competition so the ENTIRE state is about Alabama [and Auburn] football. And you couple that with the long history and the "helmet" appeal and it's a job that's just ready for the right coach to knock out of the park.
USC can't compete in the same sense because few people in California care about CFB, they are fighting with other in-state schools for recruits, and can't dominate the news because there's too much else going on [such as pro sports]. UM/ND/OSU can't do it because they're in a more crowded recruiting patch and the Midwest isn't as fertile for recruiting as the Southeast, and there's a lot more pro competition for attention. The Florida schools have too much parity, UGA has been plundered by surrounding states and deals with competition from pro sports, etc.
Granted, any other coach probably couldn't have done what Saban has done as well. As most of you point out, it's like he's tailor-made to excel at that job. He's been able to map out "the process" of exactly what needs to be done to take advantage of all the advantages that Alabama has. Saban is that guy. He understands the job in a way that others in the past perhaps didn't, and that understanding is what has allowed him to tailor what he's doing to perfectly fit the job.