[hraedon]

Responding to huge events that were unfolding in eastern Europe? I get that the Euromaidan protests are inconvenient to Russian propaganda efforts, but why is it at all sinister that a U.S. Assistant Secretary of State for European and Eurasian Affairs was present at a protest? Why is it suspicious that the US' Ambassador was present at protests that were protesting what amounted to Putin vetoing a very popular effort to deepen ties between Ukraine and the EU?

None of that, of course, is responsive to the original question of why Ukraine wasn't a friend in 2014 (in your narrative, this follows a coup and the installation of a friendly, western regime) but seems to be a friend now. Why Russia was able/allowed to annex Crimea with minimal international outcry is obvious—he either had or successfully fabricated a plausible enough claim—but doesn't fit in with the idea that all rules of conduct are applied only against enemies and not to friends.