In the Molotov–Ribbentrop Pact [0], the USSR cozied up to the Nazis with a plan for dividing up the countries unfortunate enough to be located in between them. In 1939, the USSR launched an unprovoked war of aggression against Finland.
The question of how Finland should have responded, especially from 1941 on, is a valid topic of discussion, but this discussion must be based on fact, taking into account the context of Soviet aggression and the lack of options available to Finland. Limiting yourself to what was known at the time, what would you have advised Finland to do?
Not until after they were rebuffed by Sweden and Great Britain, there was no way they were going to stand up to Russia in the longer term without outside help.
I would have done the same if it was about national survival. Nobody was coming to Finland's aid. They had run out of options. Nazi Germany was the last option.
Not exactly first or last time this has happened. Vietnam had been promised independence from the US after WWII, and tried to align with the US. When they US, renegaded on their promise and let France take Vietnam back, those fighting for Vietnamese independence ran out of options, and eventually allied with their last option, the Soviets.
Same with the founding of Israel. the UK and the US refused to take in jewish refugees from Nazi Germany. It left jews with the shitty option of declaring the state of Israel for their own survival.
People want to survive so they pick the options they have even if they aren't great. Then they get to listen to people from big countries moralize and criticize for the rest of their existence.
As an outsider who lived in Finland, I agree the paranoia about Russia is real and I disagree that it's justified. Unlike the Baltics, there is no sizeable Russian minority that "needs protection" nor is Finland in the way between a Russian exclave such as Kaliningrad.
There is no geopolitical reason to invade Finland and there is also no economical reason to do so. Most companies are foreign owned and would be pulled out of Finland the moment an invasion would start. The main natural resource of Finland is trees, which Russia has more than plenty of. Adding Finland to Russia simply solves no problem whatsoever, perceived or real.
Finns ignore this. They're paranoid because their parents taught them to, whose parents taught them to until you reach turtles.
Finns remember it happening before, for the reasons stated in the article:
> Finland mattered because of its perch above the Baltic Sea and because its southeastern border with the Soviet Union was less than 20 miles from Leningrad. If the Germans took Finland, they would be dangerously close to this Red Army stronghold.
Just substitute Russia for "the Soviet Union", NATO for "the Germans".
What T-A said. Moreover, Finland as a country exists because Czar Alexander I conquered some eastern provinces of Swedish Realm (as a weird fluke of Napoleonic wars), and then decided that they would be useful as a buffer zone for defense of St. Petersburg and also decided that it would convenient not to incorporate the government of the conquered area into Russian bureaucracy.
Meanwhile (because of another weird fluke of Napoleonic wars), soon after the loss of Finland, one of Napoleon's capable generals (Bernadotte) was given the crown of Sweden. As a Swedish monarch who had no attachments to the lost territory and possessed the strategic acumen to realize how awesome deal it was not to have Finland around, he did not contest the conquest (plus, he could use it as a point in Congress of Vienna to negotiate Norway to be given for Sweden as "reparations"). Why it was such an amazing deal? For several hundred years, area of Finland used to be a battlefield for numerous wars fought between Sweden and Russia. Ever since Napoleon and the establishment of the buffer country called "Finland", Sweden has enjoyed a remarkably long period of uninterrupted peace.
During same period of time, Finland's history could be summarized as "Finnish people not being fond of the Russian ideas how to deal with the defense of St. Petersburg". I don't foresee this state of affairs changing anytime soon.