It's pretty clear that the Suns believe their window to win a championship will open and close with Steve Nash. Nash's shooting and general skill set is not dependent on a great deal of athleticism, and he's been a career liability on defense. That being said, it's highly unlikely that his body (and his back) will allow him to play at his current level for more than another three years. So if this is the thought process, you can live with Kerr reaching for the one guy who's going to give the Suns the best chance to win in the next three years.
But there's also something far more sinister going on here, something that's not getting a lot of attention in the national media. In going after Garnett, Kerr isn't just positioning the Suns to make another championship run: he's also making sure that he bankrupts the Lakers in the process.
As I've written since Kobe Bryant's first trade demands, nothing short of landing Garnett is going to keep Kobe in town. And from this viewpoint, by snatching Garnett, not only is Kerr keeping KG out of LA, he's also ridding the Suns of Kobe Bryant.
Moreover, even if the Lakers do land Garnett (which I still expect them to), Kerr is driving the price up to the point where the Lakers will be virtually paralyzed for the next decade. To match the Suns' offer, (via Atlanta) the Lakers are going to need to throw the farm at Kevin McHale and as another BR writer added, maybe Beverley Hills too.
Not bad for a guy who was calling games last month.