Mosques and churches side by side?

St. George’s Maronite Cathedral
and
Mohammad al-Amin Mosque in Beirut,
Photo by Tom Heneghan, September 13, 2012

An interesting article by Stephen Heyman, "Designing a New Future for Syria" (NYT, September 1, 2016), tells the story of how the conservative English thinker Roger Scruton came to be mentoring the architect Marwa al-Sabouni according to a plan for restoring Syria. In the course of the article, Heyman notes that in the past:

Mosques and churches sat side by side.

I often come across statements like this one in the course of reading about Muslim-Christian relations. The supposition is that Muslims and Christians can live side by side in peace - which of course they sometimes can - but I wonder if this is the salient point about mosques and churches being located side by side. More likely, I suspect, is that Islam was operating in an Islamist mode and insisting on its dominance by construction of mosques next to churches to keep an eye on Christians and remind them who's in charge.