Justifying the killing by muslims?

Muslim Justification for killing? 

Lets not mince words here for political correctness, the absurd success of the entertainment industry has all religions justifying the right to be wrong, and the night life promotion as something mundane has been the nightmare of all religious worshipers, not just Muslims. Having cleared the stance of a religious stand point, being a Muslim yes we do not agree with the night culture and the sexual orientation of many people. But does religion specially taking Islam into picture, does it permits acts blatant acts of violence to prove a point like this?

After recent events in Orlando , an incident from the life of one of my inspirations, the great Egyptian scholar, Shaykh Muhammad Mitawally al- Sha'rawy comes to mind, as very rightly brought about by one of the whatsap forwards I recently received.
Sheikh al-Sharawy said:
I once spoke with a young man who has a mind that was quite extreme, I asked him:
"Blowing up a nightclub or immoral place with people inside, is it halal or haram?"
Young Man:
"Of course halal and permissible to kill them."
Shaykh Sha'rawi:
"If you kill them while they are disobeying God what will happen to them or where will they go?"
Young Man:
"Of course they will go to hell."
Shaykh Sha'rawi:
"Where does the devil want to take them?"
Young Man:
"Of course to hell, because it is the goal of the devil"
Shaykh Sha'rawi:
"Then you and the devil cooperate in a goal, to take humans to the hellfire."
Then Shaykh also reminded him of the Hadith of the Prophet.
When a corpse of an individual had past before him he stood up and cried, and the Sahaba ( companions of the prophet ) around him asked "What makes you weep O Messenger of Allah?" He said: "Another soul has escaped from me and gone to hell!"
Shaykh then blatantly remarked to the young man:
"Can you see the difference between you and the Prophet (may peace and blessings be upon him)? In the want of guidance for all mankind and save them from hell, you are on one side and He our prophet Muhammad (may peace and blessings be upon him) was of the other!"

Extremism has been the biggest hurdle of Islam simply because people have the knack of cherry picking Islamic rules and regulations as per their whimsical fantasy, you cannot just pick one and drop the other rule because it is inconvenient, when we believe in religious propagation, it is not a race of who gets more non muslims converted to show their boss a score card, its an act of love for the mankind as we want whats best for them in this life and the here after and we would never like to see anyone in hell. So any act of terror is counter productive to our cause of spiritual evolution of humanity. Which we believe is Islam.

May Allah bless All