Muhammed took Catholicism and removed the parts he couldn’t comprehend (should we be able to comprehend the entirety of an infinite God?). This primarily meant the Trinity–specifically in regards to the Incarnation and the Holy Spirit–and the Sacraments.
Unfortunately, this is where man encounters God in the most initmate sense–in God-made-man and through the mysteries of the Eucharist and the other sacraments. This is how man experiences and partakes in the love of God most personally and intimately. By removing these things, God was inevitably made more distant and less personal. The love of God is not as overtly present in one’s life. In such a case it is more difficult to suffer for that love.
Just as a child lacking love at home acts out disruptively in school, so are those lacking love are more likely to act out violently in the world. Those who have confidence in the love of God are better equipped to bear criticism and insults patiently because they have affirmation from God. On the other hand, those without confidence in such love, when they are criticized and not given affirmation from outside sources, they are more likely to react strongly and violently.