I've been reading about the Russo-Finnish Winter War lately, and was very interested to read that the war might have convinced Hitler to invade Russia (due to the Soviets' poor performance).
On Wikipedia it states: "Perhaps more importantly, the very poor performance of the Red Army encouraged Hitler to think that an attack on the Soviet Union would be successful."
It didn't link a source however, and I couldn't find any through my admittedly short Google search. Any insight? Maybe some sources?
Hiya!
The short answer is yes, the appalling performance of the Red Army in the Winter War was absolutely influential in convincing Nazi Germany, and indeed other states, that the USSR would be incapable of defeating a German invasion. I've discussed this directly in this post, as part of a wider discussion of the importance of the conflict. If you have any questions, I'd be more than happy to answer them - though I am about to go to bed so I'll probably only get to them tomorrow.
I hope this helps!