Why is Russia sending bombers close to U.S. airspace?

CNN - 7/28/2015

Two Russian bombers intercepted by U.S. fighter jets off the California coast on July Fourth could be seen as having raised a metaphorical middle finger to the United States. "Good morning, American pilots. We are here to greet you on your Fourth of July Independence Day," they said, according to the North American Aerospace Defense Command.

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