On top of that NATO couldn't leave any Military challenge to the Baltics unanswered. And NATO knows that. And Putin as well.
And herein lies the problem I think; NATO has continually and deliberately underfunded itself for the past 25 years, relying on the US to take up the slack. I wouldn't blame the Americans if they said 'you know what fellas, this is your problem...'
A famous American (Was it Carnegie or Roosevelt) said 'speak softly and carry a big stick', today the only stick available is a cheap knock off copy of a Harry Potter wand.