Why is the US causing trouble with Russia again?

interesting one sided responses so far! i guess some think this a movie of some sort! they are out of reality. Russia so far has shown good and peaceful gestures therefor no reason for such actions. i wonder what would their reaction be like if Russia did the same IE; in Cuba after-all shouldn't Cuba be afraid of USA? afraid for the Mobs to come back and control their country again? Russia is being pushed and these actions ere a threat to the world peace. all because a few make money out of arms race! peace