NATO proposed Ukrainian and Georgian membership of NATO in 2005-2008, in the clear knowledge that this would destabilize the situation.
France, Germany, and others were against this. The proposal began the issue. https://www.youtube.com/watch?v=SJBQikfYyKs
We then openly backed the 2014 putsch in Kiev, an open act of aggression just as irresponsible as a military incursion. CIA John Brennan, Senator John McCain, and Diplomat Victoria Nuland were there in Ukraine when Yanukovych was being overthrown. There is also evidence to show that we were involved through NGOs in overthrowing and promoting an atmosphere desiring the overthrow of Yanukovych.
This war is about more than just Putin.
Research: George Friedman, Peter Zeihan, John Mearsheimer, Peter Hitchens, Noam Chomsky (more of an ideologue), etc. on this issue. You can start on YouTube OR read their books, I guess.
These are all PhDs or experts in some fashion that I just cited. You could just read their books too.
https://en.wikipedia.org/wiki/John_Mearsheimer
https://en.wikipedia.org/wiki/George_Friedman
https://en.wikipedia.org/wiki/Peter_Zeihan
https://en.wikipedia.org/wiki/Peter_Hitchens
https://en.wikipedia.org/wiki/Noam_Chomsky
"F* the EU" said Diplomat Victoria Nuland -- knowing full well that the Germans and French would be against a coup in then-neutral Ukraine.
Meanwhile, once again, soon after the Iraq debacle: here we are getting dragged into another "war for democracy".
Russia and America turned Ukraine into a "if we can't have, burn it to the ground" situation. Further American intervention in Ukraine will just turn it into another Syria.