World War 2 was important to win for many people in the western allied (I mean Poland, Great Britain, Canada, USA et.c.) group of countries. With western allied I mean all allied countries without Sovietunion. We polish people dont like communism which Sovietunion was pushing by means of force and war (already in 1919 see link: http://www.michaelnowik.com/2020/07/24/ ... -of-world/
See my blog posts for more information about World War 2 which was started by Nazi-Germany.
Today it is important to remember World War 2 to, for example, prevent people to do bad things that can lead to war. Russia is a dictature that may be dangerous and the Nato membership is good if joined for the reason to stop wars.