What do you predict would have happened if the Berlin Airlift had failed and West Berlin had been left on its own?
If West Berlin had been left on its own, it would quickly have fallen to the communists. West Berlin was isolated inside of East Germany and could never have held out. The question, then, is what impact this would have had. As in any “what if” situation, there are many possible answers and we can never know which would have actually happened. Let us look at two possible scenarios.
In one scenario, very little would have changed. West Berlin would have fallen, but that would have had no impact on the Cold War as a whole. West Germany would still have not wanted to become communist. It would have remained in the Western camp. Communism would still have been a bad economic and political system and its shortcomings would have caused its people to hate it, just as they did in real life. The US would have won the Cold War because capitalism and democracy clearly give people better lives (and allow countries to be stronger and more stable) than communism.
In the other scenario, the fall of Berlin would have had tremendous consequences. When Berlin fell, people across Europe would have lost faith in the US. They would have felt that the US was unwilling or unable to help its allies. This would have made them more likely to go to the Soviet side. In addition, the communists would not have looked as bad as they did in real life. In real life, the presence of West Berlin made the communists look bad because people in East Berlin could see how much better things were in the West. They fled East Germany in such large numbers that the communists eventually had to build the Berlin Wall. This became a tremendous symbol, showing that communism was so bad that it had to build walls to keep its people from escaping. Without West Berlin, this would never have happened. In this scenario, more of Europe would have gone communist, or at least would not have allied strongly with the US. Communism would have been strengthened, the US weakened. The Cold War, in this scenario, might still be going on today because the US would not have seemed clearly superior to the communist bloc.
Either of these scenarios is possible, but we cannot know which one (or what other scenario not mentioned here) would have occurred.