Hopefully by the time it reaches us, we'll have an idea of its trajectory and if it'll be making a return visit at a much closer distance. If so perhaps we'll be able to do something about it. Imagine if we could get the cooperation of Russia and take a massive percentage of our combined nuclear stockpiles, and deliver them to the asteroid. Then when its at a presumably "safe" distance away we can transmit a signal to detonate and turn it into billions of small rock fragments.
Dude, that won't be neccessary.
Besides that, turning it into smaller rocks blasting in every direction would make it more dangerous. Good job.