I have an increasing suspicion that Putin may be mentally unstable. If so, nothing on the international scene could possibly be more dangerous — not ISIS, not anything. Obviously he is shrewd and there is little evidence that he is psychotic, but some of his statements and actions have become erratic and disconnected with reality. It is a situation reminiscent of Stalin in his later years.
The media are all over the place on this topic, although the bare consensus is that he is just wily and manipulative. My guess is that Putin’s mental state isn’t disabling but it makes him unpredictable and capable of making very risky choices.
For example, recently he placed his Northern Fleet on a status roughly equivalent to our DEFCON 1. This is full deployment and corresponds to a situation where nuclear war is imminent. The official explanation is that this is in response to NATO exercises in the arctic, but it is out of all proportion and seriously threatens an inadvertent mishap.
Now my concerns might be written off but for another telling point. Recently, German Chancellor Angela Merkel had a long telephone conversation with Putin. There was no language barrier since Putin is fluent in German. Immediately after ending the call, she called President Obama and expressed almost identical concerns.