Russia, US relations

I've been seeing more and more stories lately about the state of America and the West's detriorating relations with Russia. This is just the latest example. From Iran's nuclear disarmenent to the assasination of critics who happen to be British citizens, and using energy supply to blackmail small countries, Russia is become more and more aggresive. The question I have is if this is a prelude to a new arms race or cold war between powers? Hopefully the globalization of the world economy will make such a thing unlikely but it is difficult to figure out what Russia hopes to accomplish.

-John