Yep.
The Russian Military, heads-on with the Americans, at the moment, would turn pretty quickly into craters. Their equipment is as good as, and better than, American gear in some respects, but their troops, and especially their officers, I would like to take the bat to.
Generally anyone who knows about the kind of damage a sniper can do, they will react very aggressively and very quickly. Now, the kind of troops that American forces are now engaging, don't get the chance to react aggressively, and B, don't have the apparent training or equipment to react aggressively in the face of American sniper fire.
And yes, it would be impossible to put out the kind of response I described. They would probably pop smoke and manuever aggressively in the direction of the tracer origin, or find more solid cover.
Unless the weapons are set up and ready, and their crews haven't been shot (I'd be tempted to mark mortars with tracer to get our HMGs or mortars firing on them.) then they'd find it really hard to respond quickly, especially since sniper fire rarely comes from the direction that they're oriented towards: Point of most likely contact.
Eventually it would end up as:
"Igor, was that a tracer? Igor? Oh sh*t."