As an aside, our media hasn’t said much about the Muslims fighting on the Russian side . . . so you might have a point, there.
If the media go all-in on Russia, then Obama gets pressured to respond to the 23 Americans who were on board. Obama waffles because he doesn't really care and he doesn't want the conflict with Putin. The media then has to choose between covering up for Obama's indifference or to keep pressing the Americans who were killed by Russia.
The alternative is to slow the coverage overall, and back-burner the story for Americans. Low information voters won't know at all anyway, and the rest of us will just increase our frustrations, but nothing will change. Filling the void, they go back to the border story because people are still blocking buses over here.
-PJ