A terrorist attack that killed at least 20 people over the weekend in Dagestan exposes some of Russia's growing security weak spots deep in its hinterland.

A terrorist attack that killed at least 20 people over the weekend in Dagestan exposes some of Russia’s growing security weak spots deep in its hinterland.

A terrorist attack that killed at least 20 people over the weekend in Dagestan exposes some of Russia’s growing security weak spots deep in its hinterland.