The answer lies in the ability of minarets to occupy and define public space more expansively than mosques. Minarets can reach soaring heights and dominate surrounding structures. They can also be seen at greater distances as they rival other towers and buildings in the skyline. Minarets can also have, at least in theory, an acoustical presence. If the Islamic call to prayer, or the adhan, is issued from a minaret, it conveys an Islamic presence just as powerfully as the physical structure. … The possible sound of the adhan in Arabic being broadcast from minarets taps into anxieties that Muslims are taking over public space and imposing a foreign religion (and language!) on other Europeans.

Green, Todd H, The Fear of Islam_ An Intro…, loc. 631