Is it even possible to "destroy" enriched uranium? It would seem to me that the most one might achieve by blowing it up with bombs is to spread it out a little bit.
Yes, obviously you can cause it to go critical.
But that wasn’t the question. A stockpile can be destroyed by simply redistributing the contents in a way they cannot be easily retrieved.
This is I guess where the analysis gets fuzzy, where honest assessments may vary widely.
My gut instinct is that enriched uranium blown up underground (assuming it was even there) would take at most around a year to recover, by turning the site into an open-pit uranium mine. The product wouldn't need to be re-enriched from scratch, as simpler mechanical filtering could probably isolate much of the already-enriched uranium.
But perhaps it would be much harder.
The point is it is possible to destroy a stockpile without destroying the contents of the stockpile.
If you have to turn the site into an open pit mine then I am comfortable calling that a destroyed stockpile.
This kind of strike will only ever delay the process. There’s no decisively preventing anyone from enriching uranium because the laws of physics are universal.