As an American, you were obviously brought up to see both Nazi Germany and the Soviet Union as the greatest of evils.
There is certainly a case for that, with Stalin's regime actually killing far more people than Hitler's. Although Hitler's regime brought about the holocaust, attempting to eradicate an entire race.
From a British perspective, we tend to see the Soviets role as allies during that time and point to things like their liberation of Auschwitz as a measure.
So maybe it's just a perspective thing?
No my perspective is from being a historian who has studied every facet of WWII for a long time including many foreign historical sources.
Most Americans are not taught everything that Stalin did and not taught that Stalin had initially been allied with Germany.
The full outline of things I just presented is objective fact not a viewpoint of what happened.
The British and FDR regimes didn't want to fight the Soviets so praised Stalin and didn't reveal we essentially made a pact with someone as bad as Hitler. Some historians refuse to be honest because they are biased in favor of Marxism or the USSR while others want to protect the Allied actions of betraying the Poles and many of our ideals because we lacked the stomach to do anything about Stalin.
I'm not afraid of real history. I like Churchill I own books he wrote about history and thing he wrote quite well but there are still things that must be faced such as he didn't want to simply give up the entire British Empire immediately so naturally supported Soviet efforts to take the Baltics and other support on the basis that the same logic being used against the Soviets could be used to justify the British Empire being liberated.
I'm not one who is willing to sugarcoat history the simple reality is that the Allies especially the US was willing to compromise our values to avoid doing what was right. That resulted in the Iron Curtain problems which still have implications today, has major implications in Korea and especially large implications in China. The people of China have suffered for many decades under Communist rule and still do so. China has a mixed economy so it not a threat from the standpoint of invading neighbors to spread Communist but still has a tolitarian regime so the people are not free. Most people don't particularly care but if we actually did what was necessary to prevent the Communist of China takeover the world would be quite different.
The US didn't care enough about China to help though our leaders only cared enough to stop Japanese aggression in China.
If you truly study history in depth you will find that the simple things published in history textbooks leave a great deal out. Part of that is that is because a textbook is just supposed to prove a very broad overview unless it is a book exclusively to a very confined issue or point in time.
In grammar school we learned about Greece and Rome and the foundations of the Western Civilization then it leads up to Medieval Europe and eventually US history. I'm more interested in World history. I took electives in High School about other history such as Russian History. In College I took courses on Japan, China, and various European countries particularly Germany. The German courses were mainly about specific eras such as one on the unification leading up to WWI, one on Weimar, another on the Third Reich and another post War Germany. There is a huge difference when you concentrate on a specific period as opposed to getting a broad overview. The Chinese courses were mainly about Mao's China. Japan covered the Tokugawa period to WWII so provided the formation of modern Japan without being able to go into the depth of courses like Weimar that covered only a short period of time.
This is where independent reading is so important. These kinds of courses provide a good foundation to enable further learning on subjects.
The overview I provided of Stalin's actions are just the tip of iceberg but provides an accurate summary of things.
It is sheer fantasy that the USSR was doing anything to help the Allies before it was invaded by Germany and all of its actions after being invaded were for the profit of Stalin not the Soviet People. He didn't care about the Soviet people and sacrificed them for his own purposes. It wasn't just bad Soviet tactics and German skill that resulted in so many Soviet casualties. Stalin didn't care about the losses and forced actions that resulted in high casualties. He even had his own men shoot soldiers who refused to follow orders.
Hitler did some of the same things in that he virtually never allowed German forces to withdraw and when he did finally allow it then it was often too late. Leaders had to either violate orders to save their men risking being killed by Hitler or to stand their ground and get captured. German prisoners were often killed just like Soviets often were or ended up being worked to death as slave labor.
Being a soldier is never easy but the Soviet and German forces had the worst political leaders and thus were in the worst of circumstances. Hitler decided it was better for Germany to be destroyed than to surrender. Early on his stand your ground orders were seen by him as logical. He thought if they fought hard knowing they can't retreat his forces would prevail and early on that sometimes happened. But one the Allies began their counter offensives it never worked. Hitler became like those cultists who would rather have their followers die than to simply give up the cult and let them survive.
Stalin only cared about land and sacrificed over 100,000 men just for the prestige of taking Berlin. People who want to praise Stalin are doing so for motives other than to realistically evaluate his leadership.