There is no doubt that Stalin intended to re-annex Finland just the same way as the Baltic states
There is no doubt because. Besides there is good chance that you mix cause and consequences – if there were no winter war USSR probably would not annex Baltic states.
It is obvious Stalin had the aim of restoring the borders of the former Russian Empire, under him the U.S.S.R.
It is obvious because?
The historical background and stages of the Winter War are well explained elsewhere in the Internet, so I suggest you make a search and check the details
from Finnish perspective usually (not if that if there is anything wrong with that –but it is only one side)
For political reasons, Stalin needed a pretext for his attack - in the eyes of the world, it would have been just too rude to invade without any reason. The pretext was "the security of Leningrad", which led him to territorial demands on the Karelian Isthmus, in exchange for areas in Eastern Karelia. Finns could not make concessions to the extent of giving up defensive positions on the strategic land corridor to Southern Finland,
and yet they eventually did – interesting is not it?
The final staging of the pretext was "the Mainila incident", an alleged provocation by the Finnish nation (of less than 4 million) against the Soviet Union (with the population of about 200 million).
while Manila indeed was staged, I fail to see what is the size of the poplution have to do with anything? It is not exactly a boxing match.
How is it known that Stalin had set his goals further than the borders of Moscow Peace Treaty of 1940?
For one example, the offensive against Finland included a strategic movement from Suomussalmi to Oulu, in order to cut Finland in two. The outcome was to become totally different, like history tells us. But those Red Army troops participating in this operation were given clear orders that ended up in Finnish hands. The orders were, among other things:
- After the conquest of Finland, the troops must not cross the Swedish border at Tornionjoki river.
- The Swedish Frontier Guards must be saluted politely.
Military goals are not necessarily related to political ones. In 1945 USSR was in total possession of Austria, some parts of Denmark, and Norway and prior to that Iran - non of these became a part of USSR