It had less to do with Christianity and Islam, and more to do with the clash of cultures inherent to the Greco-Persian conflicts.
From a Western Civ perspective, we owe much to the Hellenistic values (especially the democratic ideals of individual voice, the right of franchise and the freedom to live one’s life without undue interference or fear).
The Persians represented the worse sort of autocracy and, like militant Islam, believed in obligation through subjugation.
I don’t see the present day conflict as being between Judeo-Christian values versus Islamic values. Rather, it is between the right to have individual freedoms versus submitting to some medieval autocratic ideal.