You really live in a weird little world if you think Russian's actions are unilateral in nature and not provoked. Let's review, since the supposed end of the Cold War:
-U.S. and partners have removed the regime of a Russian ally in Iraq
-Broken up a former Soviet client state and removed the government of a Russian ally in the Balkans, predominately via a nearly 80 day bombing campaign that violated the NATO charter on every level. In turn NATO has brought all of the "Balkanized" countries in that area under the NATO umbrella, and likely emboldened radicalized Islamic entities in the region causing a security threat for Russia
-U.S. and partners have removed a Russian aligned regime in Libya, for basically no good reason outside of the fact that they were one of the "Axis of Evil" countries (that had given up on WMD pursuit and were actually fighting against AQ)
-The U.S. has placed ABM systems around the periphery of Russia limiting the effectiveness of their only real deterrent (which has caused them to escalate their nuclear technology and increase spending on conventional forces)
-The U.S. and proxies have decimated the country of another Russian client state, again, for essentially no good reason in Syria
-The U.S. has been antagonistic towards Iran, a Russian client state
The list goes on and on. But it's all part of the "Grand Chess Game" mentality which has taken a hold of U.S. geo-strategic thinking.
Yet, somehow, we thought there would be no backlash.