I understand what you're saying, and for a stable nation that it is true, but Pakistan is not the model of stability and they don't cotton to Shia. This was a direct attack on the territory of a sovereign nuclear power, no messing around with proxies. Pakistan may have quietly been happy to have someone else bomb this faction... but still.
It seems Iran currently is like the loud, obnoxious drunk in a bar that everyone avoids until he pisses off the wrong guy, or better yet, guys.