With a fractured EU, and weakened NATO, Putin, facing an ongoing economic and social crisis in Russia, needs another foreign distraction around which to rally his people.
He funds far right anti-EU activists in Latvia, who then create a reason for an uprising of the Russian Latvians in the East of the country (the EU border with Russia).
Russia sends ‘peace keeping forces’ and ‘aid lorries’ into Latvia, as it did in Georgia, and in Ukraine.
He annexes Eastern Latvia as he did Eastern Ukraine (Crimea has the same population as Latvia, by the way).