The problem there is you can't prove anything would have come down the chimney if the preemption is successful, so people will still be unhappy.
I agree, but some of them are more obvious.
Like not giving 100 billion dollars to someone who actively wants to kill you.
A thought experiment: would the world be a better place if the US had preemptively attacked the USSR in the 50s or early 60s when it was possible to do without more than “get[ting] our hair mussed” as General Turgidson put it?