paddyann The US certainly has military bases all over the world, including a British island from which the residents were forced to move. It has also indulged in aggressive wars – the invasion of Iraq being typical. However, I think the political anxiety is that Russia and Putin, in particular, would like to re-establish the Soviet Union by the back door. Georgia, the Ukraine, Chechnya and quite a few other places have good reason to worry about this. Of course, the US has been paranoid about communism for decades.
I am not sure what you believe America is blaming Russia for at the moment, apart from interference in the recent election. The accusation of interference seems to be of a rather more serious nature than non-Scots simply telling Scots how they want them to vote.