Even so, you'd have to be a sociopath not to feel some regret at the necessity. Hell, it's even an established part of Picard's character -- recall the final log entry in "Conspiracy" where he expressed regret at the loss of life he had to inflict.
Actually, Picard did
feel some regret. When he hears that one guy screaming because he was getting incinerated by the baryon sweep, Picard stops short, and tightens his lip.
And when Kelsey's ship blew, Picard stared at the safety chip he had swiped, and if memory serves, he gives a little sigh.