I cannot stand this justification.
These acts show a basic flaw in belief systems as such, this is what is being shown by it happening within EVERY belief system. It is because our faiths become too much an identification, and you are presenting this here right now - you are defending Islam as if you are defending yourself.
For me, there is a hole in any belief system which permits the kind of distinctions which create the environment for violence of any kind.
Even if we cannot agree on what is real and what is not real, there are still a few things we can agree on!
From the Koran:
6.82 Those who believe and obscure not their belief by wrongdoing, theirs is safety; and they are rightly guided.
Look at the true nature of what the Quran is saying to you: Tawhid is oneness, throughout our lives we struggle as something separate until finally it clicks and we surrender to the one... we cease upholding distinctions. It is truly wrong - even for a man such as Jesus - to say "ana al-haqq", for it is in surrendering the individual, the sense of separation, that oneness is seen.
A true Muslim does not identify with the Quran, for a true Muslim is one who has surrendered all identifications - yet still such a one will talk, and so they use the language those around can hear.
Compare this to what is said in both the Kalama Sutta and the
Salha Sutta:
absence of greed, hatred, or delusion is the criteria for acceptance. Authoritarian dogma that propagates greed, hatred or delusion is to be rejected.
"Come, Salha, do not be satisfied with hearsay or with tradition or with legendary lore or with what has come down in scriptures or with conjecture or with logical inference or with weighing evidence or with a liking for a view after pondering it or with someone else's ability or with the thought 'The monk is our teacher.' When you know in yourself 'These things are unprofitable, liable to censure, condemned by the wise, being adopted and put into effect, they lead to harm and suffering,' then you should abandon them. What do you think? Is there greed?" — "Yes, venerable sir." — "Covetousness is the meaning of that, I say. Through greed a covetous man kills breathing things, takes what is not given, commits adultery, and utters falsehood, and he gets another to do likewise. Will that be long for his harm and suffering?" — "Yes, venerable sir." — "What do you think, is there hate?" — "Yes, venerable sir." — "Ill-will is the meaning of that, I say. Through hate a malevolent man kills breathing things... Will that be long for his harm and suffering?" — "Yes, venerable sir." — "What do you think? Is there delusion?" — "Yes, venerable sir." — "Ignorance is the meaning of that, I say. Through ignorance a deluded man kills breathing things... Will that be long for his harm and suffering?" — "Yes, venerable sir."
"What do you think? Are these things profitable or unprofitable?" — "Unprofitable, venerable sir." — "Reprehensible or blameless?" — "Reprehensible, venerable sir." — "Condemned or commended by the wise?" — "Condemned by the wise, venerable sir." — "Being adopted and put into effect, do they lead to harm and suffering, or do they not, or how does it appear to you in this case?" — "Being adopted and put into effect, venerable sir, they lead to harm and suffering. So it appears in this case." — "Now that was the reason why I told you 'Come Salha, do not be satisfied with hearsay... When you know in yourself "These things are unprofitable," then you should abandon them.'