Russia’s military build-up in Syria is aimed mainly at propping up President Bashar al-Assad and helping him reinforce his threatened coastal heartland, where he is seeking to bolster the communities that form his power base as his army falters.

The Russian escalation has ended any prospect of Assad being ousted by military force, despite the near collapse of his army in the face of rebel advances, and will consolidate the de facto partitioning of Syria, most analysts believe.

Residents of the coastal city of Latakia, a stronghold of Assad’s Alawite minority, say the increase in Russia’s military presence began as early as June and, along with it, preparations for an eventual breakup of the country of 23 million people. […]