Isn’t this the same WP editorial board that opposed US troops in Iraq ... calling it Bush’s War?
Back in 1956 Russian troops invaded Hungary, this was near the height of the Cold War era ... and the US, although there was a lot of sword rattling ... stayed the hell out of it. Same with the Ukraine ... let them sort it out we gain very little by being involved.
Sending in troops is not even in the US contingency plans as an option. That would be the worst response.
The second worst response would be to ignore the reality and do nothing.
It’s time to shoot the Bear with a bean bag and make him feel the pain. We have many options.