If properly observed, the belief in "Oneness of God" doesn't allow for arrogance in the minds and hearts of the believers. There is a logical connection between the belief in "Oneness of God," and humility and the avoidance of arrogance, pluralism, and respect for human-kind. Pluralism is not merely acceptance of diversity, but engagement with diversity and Muslims should not only tolerate and accept 'others' but be energetically engaged with them.
However, the mind-set of religious radicalism, particularly of takfiri (a brand of radical interpretation of Islam which adherents accuse all other Muslims of unbelief and apostasy) and Kharidjit (the most radical group characterized by extreme violence) groups is shaped by a kind of deep- seated arrogance which unwittingly challenges God's authority.
The arrogance of religious radicals shows itself in how they claim to know the 'ultimate' truth and to possess the 'only viable' strategy to get all things right and how they the beliefs of other people.
If one looks through the prism of the philosophy of Seerah (The Prophetic Biography), contrary to popular belief, there is no capital punishment for changing religion in Islam. All apostates were punished because of their worldly crimes. Similarly, there is no worldly punishment for blasphemous remarks.
Although tolerance and pluralism are essential in Islam and part of Islam, many (both Muslims and non-Muslims alike) believe that Islam and pluralism can't and don't co-exist. We should not blame only Islamophobia. This is first and foremost the result of a deep intellectual and spiritual crisis within Muslim communities around the world which stems from the misperception of the notion of Tawheed.
FOOTNOTES:
[1]Ali Unal, Islam Addresses Contemporary Issues, New Jersey, 2006, p.106
[2]The author adopted this concept from Abdal Hakim Murad, see for example, Mercy of Diversity,
https://www.youtube.com/watch?v=2Nyi9IUspWo
[3] Abdal Hakim Murad, Cambridge Khutbas, Reminders 2012 Islamic Equality
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