No. Its really not. Its called regular police work. And police have been identifying suspects, building cases against them, culminating in search and arrest warrants for a hundred years now without "mass surveillance".
Of those hundreds of years there has only been thirty where large numbers of people can communucate and plan operations without ever meeting. The criminals are allowed to use modern technology by the police are not?
Why should the EFF apologize for pushing for policies that make us all more free; even if a tiny handful of people die as a result?
Surveillance does not make people less free. Does an audience at a theater make an actor less free? If repressive things happen with the gathered data then that would be a problem but not the surveillance itself.
Should the police be allowed to just randomly stop and frisk you? Maybe give you an anal probe right on the street? Maybe come into your house at night, and search the place for evidence of terrorism? No? You don't think that's ok?
Physically intrusive searches are very different than electronic surveillance.
Will you personally apologize to the families of those killed by attacks that could have been stopped if these searches had been allowed?
I am not sure what you mean by this. You might mean something like "Will you personally apologize to the families of those killed by attacks that occured even though these searched were allowed?" To those families I would say "We did the best we could and used every means possible. I am sorry for your loss." Which is much better than "Your family died because I didn't want a computer scanning my email".