Russian foreign politics in the age of Putin by now I'd put down to seriously overthinking — trying to be clever, which by now tends to backfire, because the feed-back loops to the political leadership, Putin not least, don't seem to be working anymore. (I.e. this intel assets that should be "speaking truth to power" have worked out what the power would like to hear, and has to little incentive to deviate from that.) The effect seems an increasing tendency to think rivals fools, and mistaking what would be liked to be true, for what actually is. Add to that short-sightedness, looking for short to mid terms advantages. As a result Russia has become just a "spoiling agent". It might be true the Russian political leadership only thinks of this as "defense", even if a "pro-active" kind. It's still looking increasingly like this will do Russia more harm than good in the mid- to long-run. In the process it's of course supposed to screw up others. Which it might.
The biggest problem now the Russian tendency to pick up on internal inconsistencies and conflict that needs to be managed and solved in other societies, amplify and re-broadcast these with nocive effects. (It's impossible to regard these Russian actions as anything but hostile and damaging, consciously so.) The increase of the levels of distrust of democracy, public opinion making, information aren't of Russian making, but Russia could end up helping to break them in a serious way, if we're all unlucky. Paradoxically, that is unlikely to be Russia's intention. It just wants to make trouble, create divisions, the kind that might allow Russia an bit (more) of divide and conquer — probably seems no harm in it, just business as usual (and besides there's a ready go-to answer for anything: "The US did it first!") It's also nothing really bad since there are no actual consistent value or ideas as part of any kind of ideology at the centre of Russian political power. Ideologically Putin is whatever is felt to be expedient at a time or place. He changes this as regularly as weather. (Interesting arguments have been made over the Russian publics general acceptance of these sometimes almost daily shifts — none of it really matters, it's as if the range itself is sort of an advantage, Putin being everything if not at once, at least in succession, and the massive shifts between positions aren't considered inconsistent, since it works to look at them individually, not connecting them, which won't work anyway. It's all very "postmodern".)
Probably Russia also overestimates the US, and other countries it might be trying to screw with like this. It's somehow just assumed nothing REALLY bad might come from these Russian activities...
Of course, the onus is put on the US et al. to prove precisely this. Then there's a question of how it all is supposed to define relations with Russia?