I can arrive at the conclusion I don't want a global nuclear war all by myself, thanks. I'm from west Texas, and I can vividly remember the rush up to the Afghanistan war and then the Iraq war (LOL) and how they were painted as moral inevitabilities. A choice between good and evil. I wasn't alive then, but I'm sure Vietnam was the same way. America is my home and I love it, but we have our propaganda too.
Putin is an evil evil person, but there are lots of bad people in the world (see, Syria) that Americans don't whip themselves into caring about, and I don't view this an imperative thing for us to be involved in. He's not going to invade a NATO country, and even if he was so inclined, Russia does not have the capacity to wage war on another country in the near future. Whatever gains they hold onto in Ukraine (if any) are going to keep them plenty occupied for years to come. So if I was in charge, which I'm not, we'd be staying out in any militaristic sense.
I totally hear Underminer's point, and it's a good one. I just view the risk of pushing your chips into the center of the table to neuter Russia as too high. They've already done a lot of that job for us. It'll take years for them to recover economically, politically (both domestically and internationally), and militarily from this huge gaffe.