That's indeed the kind of ideas that is now floating around. I rank it in the category of Iraq coming to kill us all, with the same combination of inflating the threat and at the same time regarding the opponent as a pushover. I think Colin Powell has made some sensible comments on that. Russia is paranoid about us, about NATO. We scare them. They are a small power, we're a big one that is surrounding them more and more, and then sabre rattling is a sensible response.
That doesn't explain why they weren't rattling their sabers a few years ago. The Economist has a recent article that does offer an explanation that covers that as well The thesis is basically that domestic troubles caused by a weak economy have motivated Putin to seek ways to distract his people from domestic concerns. Specifically, he's tried to recapture the superpower position of the Soviet Union. He can't, really, because Russia isn't the Soviet Union. Without the central planning structure to force the massive overproduction of military resources, the Soviet Union wouldn't have been the Soviet Union, either.
But his people don't really realize this and, frankly, the rest of the world tends not to realize it much, either. So Putin can rattle his rusted and broken saber and the rest of the world reacts as though he was the mighty Soviet Union. Except... there is one area in which is military isn't so rusted or broken: nuclear weapons. Oh, his nuclear armament is aging and dilapidated, but it's still very real and Russia has the technological wherewithal to build highly functional nukes and missiles to carry them. Russia can't afford to build very many of them, but it doesn't really take all that many.
So, as it becomes more and more apparent that Putin doesn't really have the conventional forces to make the world treat Russia with the fear and respect that the Soviet Union got, he's almost certainly going to be making more and more use of the nuclear threat that the world can't ignore. And that will help to keep his people feeling like they're a major world power again, which will keep him in power.
Is this true? I don't know. Makes sense to me.