Stalin's Blitz 35: Nuclear Strike

Comrade General! Terrible news! 

Not only Voroshilov did not manage to capture the Oak Ridge facility, due to extremely US strong resitance. No, that's not all! US nuclear bombs came into use 2 weeks before schedule!
Second army has been hit with three high yield nuclear bombs. Army is no more!

The only powerfull Soviet force in the US is First Army under your command. However, you will face fierce resistance. US has deployed it's elite tank corps. In order to honor the assassinated german leader, Adolf Hitler, it assumes a Swastika flag and a name of Waffen SS. This is hell of an army, comrade. 

And that is not all. US possesses ability to strike from 300 km with tactical nukes. And it has deployed an elite novelty high altitude fighters - which basically render our airforce units useless. You won't deploy your airforce.

To sum up, this is it. A final challenge. Stalin orders you to stand your ground and fight to the last man, but obviously, that is suicide.
Retreat, comrade. Retreat to the West Coast. Maybe upon reaching San Francisco and taking it's populace hostage, you can negotiate with the US....? 