For one thing, shattering it without sufficiently deflecting the trajectory of the shards.
The now radioactive shards.
I think this is an agency worried about its mission and its budget.
But, at least it ensures that all the shards are radioactive.
This whole thing about nuking an asteroid sounds like a side show to strengthen the UN and glowBull governance.
Exactly!
I'm not a physicist, so maybe space behaves differently than I think, but I would have a pessimistic attitude toward deflection in general.
On earth, a big explosion pushes earth and debris and air molecules -- and these all push more earth and debris and air molecules. We've all seen blast waves from nukes and whatnot. You can knock down a building a mile from the blast site.
In space, there is no dirt, no debris, and no air molecules. I don't know how much "pushing" can be affected in a vacuum.
If the explosion takes place on the surface of the asteroid, I think Newton's Second Law would move it significantly. That would be good. But, if the explosion takes place "nearby" I would worry that it might have almost no effect.