What is the Achilles heel of Islam?

The Achilles Heel of Islam is that the Quran denies the universally approved fact of Jesus' crucifixion. The Islamic concept of God is also not absolutely perfect, since Allah loves conditionally, partially, according to the Quran. And Allah is a single deity, with no object of love prior to creation, which is a necessity for an absolutely loving God that can't be self-centered and needs someone to gift his love to. Creation can't solve the issue since it's not necessary, but an act of free will, while the love our Lord possesses is his nature and essence.

The denial of Trinity by Mohammad is utterly plausible and could have been a reaction of any Christian to the way Mohammad knew the Trinity : Father, Son and (!) Virgin Mary !!! Anyone would deny it, how would a finite Virgin conceive a deity? The problem is that in those days Our Lady was called 'The Mother of God',  which lead to a misunderstanding claiming that a finite Saint has conceived an infinite God, which is logically incoherent. She was called so as the Divine Power rested on her to be the Mother of the HUMAN nature of Christ, not the DIVINE, which always existed and is infinite. Jesus possesses two natures, which makes the Christian God EVEN FULLER AND MAXIMUM!