Bay of Pigs, huh? Not a very good comparison. I’m sure you can find better.
Why not? I think it's a pretty good comparison. The US Government identified, recruited, armed and trained Cuban opponents of Castro. The Russian government identified, recruited, armed and trained Ukrainian opponents of the Kiev regime. The relative merits of the two interventions aside, it seems like pretty much the same move by powers who were trying to effect regime change in a neighboring state, but didn't want to get their hands too dirty by directly invading.
The major difference I see is that there seem to be somewhat more Russian boots on the ground in Eastern Ukraine than there were American boots on the ground in Cuba, but any difference is marginal and hard to really measure. The overall approach seems to be the same. And there’s no reason to believe that regular Russian Army units are engaged at all (because if they were, the Ukrainian Army wouldn’t be winning!).