I mostly agree with the above post, but since the Bataan Death March happened early in the war, after the conquest of our colony the Philippines, it was really our first direct exposure to the Japanese Code of Bushido and the way in which they devalued humans who surrendered.
The brutality of that march, along with the surprise attack at Pearl Harbor on a Sunday, and the suicide attacks later in the war did shape US attitudes towards how the war should be fought. Some even argue it contributed to the decision to drop the atomic bomb, both as revenge for things like Bataan and Nanking, and as a way to save American lives from an army that would fight to the last man.
This incident did not really have much of an impact, if any, on the actual outcome of World War II. And it did not have much of an impact on how the war was fought. The only real importance of this is in how it affects the way we remember the war (and of course it affected the people involved, like one of my great-uncles who died in it).
The Bataan Death March happened after the US and Filipino troops surrendered their last position on Luzon in the Philippines. This was the island fortress of Corregidor. After the surrender, the troops were marched 60 miles or so off to a railhead that would bring them to a prison camp. Along the way, many of the prisoners died because of the brutal way they were treated.
This became important as a symbol of Japanese brutality during WWII.
Bataan Death March refers to the forced march of of USA soldiers taken prisoners by Japanese in Philippines. On April 9, 1942 nearly 75,000 US and Filipino troops at Bataan Peninsula of surrendered to the Japanese. Most of these soldiers were made to march to prison camps located about 105 kilometers away. The soldiers faced gross mistreatment from the Japanese during the march. As a result many prisoners died on the way because of diseases, exhaustion and other causes. Different authorities have placed the number of causalities between six thousand and eleven thousand in a span of about one week.