One of the reasons I avoid attending Friday congregations at mosques is a specific ritual supplication uttered by Imams at many mosques in Canada and around the world, just prior to our formal Friday community prayer, the Juma’a.
In the supplication, the cleric prays to Allah for, among other things, to grant “Muslims victory over the ‘Qawm al-Kafiroon,'” the Arabic phrase that lumps all non-Muslims — Jews, Hindus, Christians, Atheists, Buddhists and Sikhs — into one derogatory category, the “Kuffar”, or non-Muslims.
This supplication is not obligatory. Not uttering this prayer would in no way adversely affect the holiness or solemnness of the collective community prayer.
I have long argued with my orthodox and conservative Muslim friends and family that at least when living among non-Muslims, we should avoid praying for their defeat at the hands of Muslims.