Fifty?
Five hundred?
Five hundred million?
As many as it takes? Or is there a limit?
What if the conflict kills five hundred people on your side, and fifty on theirs? Do you also consider that a good exchange?
Everyone who was killed in this attack was willing to die to kill innocent Indians, civilians included. So, from that standpoint it is a completely justified attack.
Terrorism isn't going away itself. One or both the nations need to take action on them.
As Einstein said, lunacy is doing the same thing again and again and expect a different result.
Anyway, that expression is misattributed:
They don't let us live in peace. They try to attack us everyday. They wage a proxy war against us.
We are seriously re-thinking if their nuclear weapons should be taken into account anymore.