A divided Europe, with the leaders of France, Hungary, Poland, Slovakia, and others now pro-Russia, anti-EU, and funded by Putin, overrule calls for sanctions or a military response.
NATO is slow to respond: Trump does not want America to be involved, and a large part of Europe is indifferent or blocking any action.
Russia, seeing no real resistance to their actions, move further into Latvia, and then into Eastern Estonia and Lithuania.
The Baltic States declare war on Russia and start to retaliate, as they have now been invaded so have no choice.
Half of Europe sides with them, a few countries remain neutral, and a few side with Russia.
Where does Turkey stand on this? How does ISIS respond to a new war in Europe? Who uses a nuclear weapon first?