As expected, the decision by Kosovo to declare independence is dividing the international community. Russia is fighting to block official recognition of the new State. Russia used its power in the UN to create an impasse on the issue of recognition. To get around this, nations have begun to recognize Kosovo (an American protectorate in the Balkans) one by one. Most EU Countries have chosen to recognize the breakaway Republic.
Moscow is concerned about Serbs who live in Kosovo who may suffer from the independence declaration. Moscow is also concerned about its own breakaway Republics in Western Russia declaring independence after being encouraged by Western support of Kosovo. Russia has always seen Kosovo independence as unnacceptable, and has expressed its willingness to fight to prevent its own breakaway regions from doing the same. Russia sees the U.S. and the EU as instigators and supporters of these independence efforts in Kosovo and with regions on its Western flank and Moscow sees this as a threat to Russian national interests.
This will certainly work to keep the new Cold War going. The U.S. fought two wars in the Balkans in the 1990's which led to this point. And it was the U.S./NATO attack on Yugoslavia in 1999 that spurred a resurgence of Cold War rhetoric between the U.S. and Russia. That is the point when relations began to deteriorate (again) between the two Countries.
The U.S. has thousands of troops in Kosovo as part of the NATO KFOR mission.
Hear Report from NPR