
I'm quite sure that «идем» is present time, not future. So not "We'll firmly march forward", but "We firmly march forward". As if they're doing it at the same time as they're singing this. Otherwise, if it was future time, it would be «пойдём».
I don't understand how you came up with that translation of «Рубеж наш назначен Вождем», I think that it should be translated as "The Leader designated the border for us". In the meaning, that he has told us that the enemy mustn't go further. "The Leader" being Stalin, of course.
You say in footnote 2 that "Red Star" refers to those who are in the Kreml, but I think it literally refers to the Kreml's appearance. It has red stars on the towers, see for example this picture: http://www.nightcitylights.com/Blog/201010/21/011.jpg
«Не счесть богатырскую силу» would actually be translated as "Our heroic strength cannot be counted".
The third verse has some more aspects: «Отплатим мы страшной ценой» is not just "We will pay back", but "We will pay back with a terrible price". And «Для счастья своими руками» is not just "For our own joy", but "For our own joy, with our own hands".
And I can't agree with you on your opinion about the battle of Moscow and Stalin. I mean, what else was he supposed to do, retreat and let the fascists destroy the country?
I just felt like translating it. Good song if you put history to the side. But when history is dragged into the equation it really gets kinda depressing when you realize the fate of those men who defended Moscow and the heroes of the battle being sent to the Gulags. I hate the Stalinist Album for this reason. I have deep internal conflicts with the Stalinist Album because of the revolting actions of that coward. But I cannot change history nor the facts, and my political philosophy is to translate music, to take one's message and make it available to all, and I felt this should be done, all though I just want to make it clear, I'm not going to do too many songs from the Stalinist Album for my own emotions and politics interfering with my interpretation. It is hard to feel upbeat and enlightened by a patriotic song about those who will defend Moscow to their lives only to realize it wasn't the fascists who took the lives of soldiers but in the end the leader they threw their lives to. /rant