It's funny because if you go to WWI you can see a pretty clear example of what happens when socialists pitch in with the imperial powers in their power struggles. It doesn't end in success for the left. WWII is a special case because it did in fact feature a socialist option and so a contribution to the war effort meant a contribution to the protection of that fledgling socialist project. That said, if you were a commie in either the UK or US who aided in the war effort what did you get in return? Liberal powers drafting Nazis into the new NATO organization and disenfranchisement via red-scare within your own nation. That's why my point is that denazification doesn't exist under liberalism, the fascists are born from material conditions that liberalism cannot by definition change. So even a liberal victory over fascism ultimately results in fascism re-emerging at a later date. It's only redistributive and socialist political projects that stomp out the root of fascist ideology and actually complete the goal of denazification. As an individual in war time? Help those around you and protect the people you can. But as a larger left project getting co-opted into the liberal project of imperialist wars doesn't do us any good