there was only really 1 type of missile that had a chance to shoot a blackbird if it was fired under very specific and tight conditions and timings.
a radar lock is one thing, a kill is another.
as the comments on the article cite, the best probability of a theoretical kill on a blackbird was accomplished by Sweden using Viggen interceptors. Theoretical because they didn't fire.
The USAF acknowledge this with a congratulatory fax to the Swedes.
