At the level of the Ten Commandments, for the Islam religion we hear about proclamations for killing of infidels, stoning to death, and eye for and eye, disfigurement of women, etc. We do not hear from moderate Muslims. Hence, we tend to be suspicious of all Muslims. We can't tell before the fact whether a Muslim is a zealot or not. The after effects of the wars in Afghanistan and Iraq will be with us for decades. The mistrust of Muslims, and vice versa, will also continue if not increase.
I think it would be judicious for principals on both sides to agree that it is not in the best interest of either side to erect a mosque at the proposed site in the near future.