> To be fair Crimea does have a majority ethnic Russian inhabitants. Wikipedia lists Crimea's demographics as 65% while others were lower at 58% or thereabout. Given many of those Russians were there from the Soviet era or direct descendants, it doesn't seem too crazy of a claim. The US and NATO countries have done worse for less. Now invading Ukraine? Thats another thing altogether.

What do you mean "now invading Ukraine"? Russia already did that, when they invaded Crimea, which is Ukraine.