So? That's in their backyard. They just pulled themselves into the middle east vortex.
It doesn't change anything. You think Sunni militants care about a "backyard" ? For them, it's the same thing : it's their land and russians are killing their people. Jihadism is an internationalism. Back then, like today, money was already coming from Saudi Arabia.
Russia have seen worse when it comes to terror attacks. People seem to forget that Russia is itself a country with a HUGE muslim population. In the 80's, russians diplomats were already being targeted by militants. Look at what happens in Lebanon in 1985. Russians are going to be pissed by this, but it's not a surprise for them. When you go to the Middle East, you know this type of shyt come with the territory.