Professor Thomas Childers, on my recorded lecture set, says that the Russians deliberately held back and let the uprising be crushed in order to facilitate their control of Poland after the war.
Yep, that is absolutely true. The Russians even broadcast a message to the Poles telling them to rise up and they would soon be there. Of course they had no intention of doing that.
Normally, as a believer that military operations end when they reach thier logistic limit, I’d be inclined to believe that the Soviets were unable to assist the Poles. Rokossovsky’s armies covered hundreds of miles and participated in two major offensives, Bagation and Lvov-Sandomierz. Bagration had played out and other than grabbing a few bridgeheads in areas that were lightly defended, the Soviets were stopping at the Vistula. Repairing the road and rail network behind them, and getting supplies and new equipment to the front, wasn’t going to get done before the autumn rains. So for all practical purposes, the gigantic Soviet summer offensive is over on this part of the front.
However, what Stalin did at this point is proof that despite thses limitations, he welcomed the opportunity to watch the pro-western Poles and Nazi Germans kill each other. The fact that he incited the uprising, did absolutely nothing to help, and blocked Anglo-American attempts at help issufficient proof that he used this as an opportunity to exterminate potential anti-Soviet elements in Poland. He would have done this anyway, but this way he got Hitler to do it for him.
If Hitler had been a little more broad-minded, he could have used this situation as the one real chance to split the alliance arrayed against him. He could have withdrawn from the immediate area of Warsaw and allowed the Poles to set up their home government. Even better, he could have allowed safe passage of the London Poles to Warsaw to take over, forcing the Brits to recognize them as the official government. Can you imagine Stalin’s reaction to a hostile Polish government, recognized by Great Britain, interposed between his armies and the Germans? What do the allies do when the Poles deny access to the Soviets, as they probably would?
The diplomatic situation between the UK and USSR was dicey enough over the Polish Question. Had Hitler taken adavantage of it, it offered the only real chance to split the Grand Alliance and salvage something other than total defeat.