Mike Tomlin is the head coach of the Steelers because he's black.
He's a good coach, but the reason he beat out the in-house contenders of Whisenhunt and Grimm was because they were white and the team's owner and instigator of the "Rooney Rule" couldn't pass up the opportunity to hire a black coach. Think about it, would Dan Rooney, who lent his name to the rule that requires at least one non-white person be interviewed for a head coaching vacancy, decide to then not hire that candidate? No, because then he would have been excoriated for hypocrisy: that he wanted to interview but not actually hire them. He was caught in a trap of his own making and forced to hire Tomlin.
He was fortunate enough to get someone competent, but I think it's clear enough that Whisenhunt would have been an even better choice. Tomlin took an already successful team back to the play-offs and then to the Super Bowl. Whisenhunt took a perennial punching-bag, a team that was synonymous with failure and ineptitude, and turned it into a champion.
So now that the brilliant team owners in the NFL have enshrined racial prejudice as a policy in their league at the position of head coach, they seem to think the appropriate step is to expand their policy of judging people by the color of their skin and mandate that non-white candidates be interviewed for General Manager vacancies as well.
(In that ESPN article I linked, the only possible reason to note that Rooney is a "lifelong Republican" is to attempt to forestall arguments against this considered expansion of institutional racism. Since Rooney is going to serve as an ambassador in a Democrat administration and, more importantly, endorsed and campaigned for that self-same Democrat for president, I'd say that he's a little less than a "lifelong Republican". It would be more accurate to say he was "a Republican until the most recent presidential election.")