Your history is seriously fouled up. The EU didn’t instigate the takeover of the Crimea and the US is the one who talked Ukraine into surrendering its nukes all those years ago in return for a worthless security guarantee. More recently Obama signaled to the world that we were open for pretty much any aggressive move they wanted to undertake. Blame where blame is due. The buck stops at the White House.
Uh, no, not Crimea, Ukraine! EU factions backed and paid for the takeover of Kiev and the country of Ukraine, the whole area is infested with corrupt officials and politicians.
The nukes were taken (started under George Bush IIRC) because it was certain Ukraine had no way to safeguard them and they would have ended up on the black market, sold to the highest bidder.
Ukraine wanted to be recognized as a sovereign independent country, and this was the deal for that to happen.
As witnessed by the events in Ukraine over the last 3 years, this was a VERY wise decision.