Changing History

If you could change one historical event, which event would you choose, and how would you change it? Why would that change be for the best?

Changing history is not something to be undertaken lightly. There is no real way to know what might result from even the most seemingly insignificant change. Consider if merely the wall color had been different during the Cuban Missile Crisis. What if the walls of the White House had been an aggressive color such as yellow, orange, or red. Would the outcome have been the same, or would we all be bits of radioactive waste right now. If even such a small change has the potential to make such a drastic effect on the course of history, then how can we even consider large changes?
But of course it is always possible that even the most glaring changes could result in very little noticeable effects. If Columbus had never found the Americas, for instance, what would the world be like now. I would be inclined to think that it would be very much the same. Some European was bound to find America around that point in history. That time period was one of great exploration by European powers, and it is highly unlikely that Columbus, even if he failed, would have been the only one to venture far enough west to find the continents that we now call America. With that being said there seems little point in trying to make a change in order to create a specific course of events.
Take for instance the Holocaust. How would one go about trying to prevent the Holocaust? Is there a single event that could possibly prevent such a horrible tragedy? Perhaps if Hitler had never existed things would have been different. But there are no guarantees. Much of Europe was extremely anti-semitic at the time. It is entirely possible that even without Hitler some other ruler would have implemented much the same policy. Another question that is raised by eliminating Hitler is World War II. Would it have even happened. Would it have been worse, better, much the same? Without German participation in the war, it is quite possible that it would have been a showdown between the United States and Russia. If so would there have been a Cold War afterwards? And without a Cold War would there have been a space race, or the development of the atom bomb?
Since there is no real way to know what the outcome would be, the only real purpose in changing an historical event can be for experimental purposes: to find out what would happen. For this reason I would choose to eliminate Hitler's existence. This would be a very interesting change for many of the reasons listed above. It also brings up the question of individual impact on the world. Hitler could be considered one of the most influential men of the twentieth century, but would his non-existence really change anything significantly? It is possible that all of the major events that we are familiar with would have occurred with some other maniacal dictator leading Germany. But it is also possible that the scenario described above in which the Cold War never happens could be the outcome.
These are only two of the infinite possible outcomes of changing this one aspect of history. Each on is equally as likely as the other despite how drastically different modern life would be based on the different paths. So the real lesson here is that there is no real point in changing an historical event. There is no way to ensure that the desired outcome will result, and even if it does there is no way to know how that might change the rest of history up until this point. That is why I would chose not to change history even in the most minor way, but if I had to make a choice I would make one that I thought would have the most experimentally interesting possible outcomes.