>>88554188That's a very simplistic view of the Second World War. Germany invaded Poland because they refused to return land taken from Germany after the First World War, which split Germany proper from Prussia. It is likely that they refused because Britain and France emboldened them by guaranteeing their independence should Germany invade, leading to them refusing to hand over the land Germany desired. Germany claimed that German populations were being oppressed in Poland, and that Poland actually attacked first, and invaded. Britain and France promptly declared war on Germany, which escalated what would have been a small regional conflict into a worldwide conflict. The UK and France were not attacked at that stage.
Also interesting to note is that the USSR also invaded Poland when Germany did, and massacred some Poles, which they later attributed to Germany. They had also invaded Finland, taking territory from them previously, and had invaded the Baltic states of Estonia, Latvia, and Lithuania.
Germany invaded Belgium and the Netherlands in order to avoided french fortifications that would have prolonged the war. They succeeded in occupying France, and retaking areas which had German majority populations that were lost after WW1.
Germany invaded the USSR for a variety of reasons. However, on potential reason is that they became aware that Stalin was planning to invade and conquer not just them, but all of western Europe.
Essentially, World War 2 was overall a pretty pointless war. It created a bleak geopolitical situation that is still very apparent today. It broke the back of Europe, leading to it's decline, and the rise of the US and USSR as the pre-eminent superpowers. Sure, the Nazis were not the nicest people, but neither was the USSR, or most of the other powers. Eugenics was practiced in the US, British, French, and Belgian empires created vast colonial holdings through invasion and geopolitical meddling, and the USSR killed and oppressed plenty.
