Still Nobody resigned?? No hope from ruling government nawaz sharif PMLN, but waiting for resignation of any PTI minister responsible for security or health measure.
You're assuming this is a failure of security. But that's not true. This is not a "security lapse", as if someone fell asleep on the job. This is a failure to address the roots of the problem.
Security measures are a form of self-defense. They are meant to be a last-resort mechanism. If they have to actually be used, then that means that a hundred things already went wrong beforehand.
I have studied self-defense. If someone tries to attack me, I think I could deal with it well, and all praise is to Allah for that. But using physical self-defense measures against an attack is only a last resort for me. If it ever happens, it will only be because I did a lot of other stuff wrong, and made many other mistakes: insulting someone, going to a bad area of town, having an affair with someone else's spouse, etc. etc.
Security measures for dealing with terrorism are similar. Policemen, alarms, armed guards, SWAT teams, covert intelligence work, military operations are all great security measures. But these are all meant to be last-resort measures, not our primary way of dealing with the issue. When we have to use these to deal with terrorism, it means that all kinds of other stuff has gone wrong to put us in that situation: leadership without merit or accountability, poor educational systems, lack of social justice, foreign backing for insurgencies, corrupt judiciary, and so on.
If you want resignations, look at these areas where the seeds of terrorism get planted. Prevention is always better than trying to cure a disease.