Gist of this Washington Post article is, No. Just Russian posturing.
Against that are a host of (Not Ready for Prime Time) internet sites with a grain of fact and a cup of speculation;
Independent – Russia’s top propagandist says US behaviour could have ‘nuclear’ implications … has been a ‘radical change’ in relations between Russia and the US (Another British paper, but more main stream)
Whoa, ABC and NBC?
Ah, another internet crazy site.
Daily Beast – Russia Is Building Fallout Shelters to Prepare for a Potential Nuclear Strike [includes information not seen elsewhere] (oh! I didn’t know this: The Daily Beast is owned by IAC, where Vice Chair of the Clinton Foundation, Chelsea Clinton, serves on the board of directors)
If you believe that the nuclear destruction of the USA is Barack Obama’s end game, then worry. But if you believe that Barry’s favorite hobby is kicking the USA’s ass and he has mountains of Kobe beef to consume and miles of golf to play then don’t.
Hillary however, is another matter.