As the space between molecules in a gas sample decreases, the tendency for the behavior of this gas to deviate from the ideal gas laws.

Explanation:

In real gases, there exists force of attraction between the molecules at low temperature and high pressure. This is because at low temperature there occurs a decrease in kinetic energy of gas molecules and high pressure causes the molecules to come closer to each other.

As a result, forces of attraction increases as molecules come closer to each other and therefore, gases deviate from an ideal gas behavior.

And, at low pressure and high temperature there exists no force of attraction or repulsion between the molecules of a gas. Hence gases behave ideally at these conditions.

Therefore, we can conclude that as the space between molecules in a gas sample decreases, the tendency for the behavior of this gas increases to deviate from the ideal gas laws.

I'll assume that's a thesis statement meant for argument or debate.  An argument could be made on either side, depending on your point of view.  

On the one hand, the United States and the Soviet Union had dramatically different worldviews.  The US system of democracy and capitalism was at odds with the USSR system of totalitarian rule and communist collectivism.  The two nations were allied only for the sake of defeating Germany and Japan in the Second World War, and were in opposition to each other in about every other way.  Following the war, they became bitter opponents in the Cold War.On the other hand, the USA and the other Allies in World War II needed the help of the Soviet Union in order to defeat the combined threat of Germany and Japan.  The USSR suffered millions of casualties due to the war -- more than any other nation.  They bore the brunt of the fighting against Germany, even before the US entered the war.  And President Roosevelt, while not in agreement with the governing philosophy of Joseph Stalin, still thought he was someone that could be worked with cooperatively.   (When President Truman took over after Roosevelt's death, he did not share that same view of Stalin and the USSR.)

So the matter can be argued from both sides.  Pick your side and write a strong essay!