NATO is already one or two day’s drive from Moscow from Latvia and far close to St Petersberg. Putin wants Ukraine period. That was the gist of his pre war speech. If he gets it the immediate result will be to place four more NATO countries on Russia’s borders. That will bring the number to nine counting Turkey and Norway.
That Baltic invasion route is not going to work. You need the terrain you find on the Kiev, Kursk, Moscow route of attack. That is why the Battle of Kursk involved such massive amounts of armor, they could easily maneuver over the terrain. Although you will end up seeing a larger number of tanks on the NATO Ukrainian/Russian frontier, the second battle of Kursk will never take place. The Russians will do what we would have been forced to do had they decided to massively roll through the Fulda Gap. After Reagan and Thatcher placed intermediate range nukes in West Germany we would have nuked them. Russia, hopelessly outgunned, would do the same to NATO forces rolling across the Russian border 300 miles from Moscow. The 350 new Polish M1 tanks could be on the Ukrainian/Russian frontier in less than a day. You do know they’d be redeployed by highballing trains.