Those people that you say with such certainty not to be Muslims.
They sure seem to disagree and to emphasize that disagreement.
If I told you I was a rabbit yet common sense, science, biology and all the other factors which make a rabbit a rabbit, were against me, would I still be a rabbit? Or would you think I was disillusioned?
With that in mind, just because someone claims to be a Muslim or claims to carry out certain acts for the sake of Islam, does not make him a Muslims or a religion champion. It's as simple as that.
The evidence shows that most of these people, largely young men, are disillusioned men, marginalised by western society, lacking jobs in many cases, lacking family, finances or friendships in many other cases, who are brain washed by organisations which have been shown to be promoted and funded by western governments or intelligence agencies.
If you study the cases of many if not most of these so called religious extremists, you will find that they are not and never had been, religion in the first place. 2 terrorists from Britain, leaving to fight for ISIS in Syria, 6 weeks before they left, bought 2 books off Amazon: The Quran for Dummies and Islam for Dummies.
Anyway, I've spoken to you about this before and provided evidence from intelligence services who know these terrorists are not religious extremists but rather novices and you still don't like to believe it because of your own personal biases. So, I don't think there is any point in me explaining it to you any more.