ANN ARBOR, Mich. -- On the plane back to Michigan -- a journey that took a few hours or almost three decades, depending on your perspective -- Jim Harbaugh looked at his kids.

“They had some stocking caps from my kids from the ‘M Den,’” he told SI.com. “My daughter Addie was wearing a scarf. We had a gift bag of some hats and things. When I saw my kids in the maize and blue, it was a terrific feeling. It took me back to a place …

“I remember going to Moe’s Sporting Goods, and I’m looking at my kids with their stuff, their scarves, their Michigan gloves ... I would have loved to have that as a kid. You would hope you would get something like that for Christmas.”

This is the pull that lured Harbaugh back to Ann Arbor -- indefinable, and ultimately undeniable. It was not an easy decision, and it was not a quick one. Jim’s father, Jack Harbaugh, told SI.com he did not believe Jim would go to Michigan until one week ago.

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They were talking about the possibilities: The NFL was still out there, with the promise of more money than Michigan would offer, and a chance to win the Super Bowl that barely eluded Harbaugh in San Francisco. Michigan people believed they would get their man, but the truth was, nothing was signed. Like many who know Jim well, Jack believed that once his younger son went to the NFL in 2011, he would never go back to college.

But then Jim started talking about all the places he went as a kid, when his father was an assistant coach at Michigan -- about St. Francis of Assisi Catholic Church and Tappan Middle School and Pioneer High School. He talked about his time spent in Bo Schembechler’s office and his memories of growing up in Ann Arbor. He imagined what that would be like for his own children, walking the same streets and eating in the same ice cream parlors.

“Then I kind of sensed this was something realistic,” Jack said, “something he really, truly wanted to do.”

You hear so many coaches talk about doing what’s best for their families when they are really trying to fulfill their football dreams. Harbaugh found a way to do both. His young children can have the Ann Arbor childhood he had, and he can shoot for Michigan’s second national championship since 1948, which would mean as much to him as a Super Bowl.

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Harbaugh said the decision came down to “several reasons, but it’s a decision I made with my heart. I’m very humbled, very honored. And ready to work and do my part. I want to do a good job. I want to be good at it. I want to be good for Michigan. That’s really the things that I really feel …

“I can barely hold a thought, I find I’m so excited.”

He leaves a situation in San Francisco that got needlessly ugly, with the owner, Jed York, ultimately forcing him out. There were stories about players hating him and him being impossible to work with, even though anybody who watched his San Francisco finale could see that the 49ers played as hard as any team in the league for their coach, to the very end.

I floated this theory to Harbaugh: When you are painted as something you’re not, you want to go where people know who you are.

“There is probably something there,” he said.

Make no mistake: This journey does not end now. It begins. As a Michigan player, Harbaugh famously guaranteed a victory over Ohio State, for the simple reason that he had always dreamed of leading Michigan to a Rose Bowl as a kid, and Michigan needed to beat Ohio State his senior year to do it. As a coach, he is wiser, and less impulsive.

“We’re not making predictions,” he said. “It’s not about describing what we’re going to do. It’s going to be doing it. We will have very high expectations for day one. Have a great first day. See if we can’t be better tomorrow than we were today.”

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I asked about his reputation as a short-timer, a coach who makes teams better and then gets out. He said: “Criticism is ... it can wear some people out. It doesn’t [do that] to me. Somebody is always going to say something. I don’t want to go down the road.”

The simple truth about Harbaugh and this short-timer business is that there is precious little evidence of it. He won at the University of San Diego and left for Stanford. He turned around Stanford and left for the NFL. Ninety-five percent of coaches would have made those same moves. The only unusual line on his résumé is his exit from San Francisco after an incredibly successful four-year run. But Harbaugh wanted to stay with the 49ers until ownership left him no choice.

Yes, there are those who say his style grates on people, but there are many who say it wins, and he is far more approachable and likeable than his critics would like to admit. The brash young quarterback has become a savvy, veteran coach, and Michigan will win big on his watch.

There is no reason to worry about Harbaugh leaving for the NFL, just as Ohio State did not worry about Urban Meyer’s health when it hired him in 2011, and Michigan State did not panic when Mark Dantonio had a heart attack a few years ago. Tomorrow is promised to nobody. Why worry? Michigan is a better, more exciting program now than it was last week. Harbaugh won’t leave until he has his alma mater where he wants it.

He coveted the job in 2011, but Michigan athletic director Dave Brandon botched it, and Harbaugh decided to try the NFL. He was happy there, and people who know him well expected him to stay in the pros. But there were moments, looking back, when you could see him on the road back home, even if he didn’t realize it then.

Two years ago, Michigan held an alumni meet-and-greet “practically in my neighborhood, five houses down,” he says. Harbaugh went to hear men's basketball coach John Beilein speak. He did not know Beilein, but says he “was so impressed with him. That guy is a stud.” Beilein only talked for 15 minutes, but in that moment, Harbaugh was not a pro coach or potential Michigan savior. He was just an alumnus.

“That’s all I was,” he says, “getting fired up, listening.”

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That feeling never left him, and understand: If he were single, or if his kids were all grown up, maybe he doesn’t make this move. Then it would be mostly about a job, and the NFL has a lot of appealing jobs. This was about a way of life, winning at Michigan while his kids drop by the office, the way he did when his dad coached under Schembechler. It is not just about beating Ohio State, but about doing it with his whole family along for the ride, in the town where he first dreamed of doing it.

People don’t like to think of Harbaugh this way. They see his face on the sideline, his deliberately poor fashion choices and imagine him as some crazed, hyper-intense, football-only zealot. He describes his interests as “faith, family, football,” but in truth, he converses just as easily about politics or books, and this week he told me he feels like Morgan Freeman's character in The Shawshank Redemption: I think it's the excitement only a free man can feel -- a free man at the start of a long journey whose conclusion is uncertain.

“Red” Redding was going toward the Pacific; Harbaugh is leaving it. He hopes he is free now, free from the political games he doesn’t like to play. He isn’t, really.

Michigan can be an extremely political institution, even in athletics. But Harbaugh is already more appreciated in Ann Arbor than he ever was in San Francisco, even in his best days there. Michigan, unlike the pros, and unlike many colleges, craves stability.

As a senior at Michigan, Harbaugh sat in Schembechler’s office, and the coach relaxed for a moment, talked about all that Jim had accomplished, and said, “Your dad must be so proud of you.”

Years later, Harbaugh told me he remembered sitting there that day and “feeling so warm.” I asked if he felt that way now. “Yeah, in a way,” he said. Jack Harbaugh is so proud, and so happy. Jim Harbaugh is back. Michigan will be, too.