@Prejudice: It's not very simple. Easy answer would be, we had to choose between two bad choises and Germany seemed much less worse. Of course we've had our forever distrust towards east, but Soviet Union then was expansionist, aggressive and very unpredictable. Also we had lost territory in Winter War (31.11.'39-13.3.'40) and were more than willing to claim them back. Why? We lost significant size of fertile farmland and rich woods. And we shouldn't forget the will of revenge. Also, Germany was only realistic partner to trade along with Sweden. Baltic Sea was surrounded by four independent nations: Finland, Sweden, Germany and Soviet Union. And I put them in order with whom we'd like to trade. Also Germany offered great improvements to our army, modernizing both personal and heavy equipment. Why not trade with western world? Simply because it was impossible, mostly because Germany wouldn't had let us. And your saying "clearly able to fight off" is actually very false. Without political pressure from west to make peace Soviet Union would had taken Finland over.
@A.J. Raffles: Actually Il-1 never entered production if I remember correctly...
And indeed Li-2, named by it's "designer" Boris Lisunov, is C-47 Skytrain variant, which was used both to troop transport and as a bomber. I know it's cargo capacity must have been less than C-47, over 4500kg, but how much and what was it's bomb carry capacity.
...70 years... LOL