Watch a few too many M*A*S*H reruns, Trudeau? (Yes, I know this is a decades-old rerun.) Whatever might be said of other wars, the Korean War was absolutely necessary. As the victors over Japan in WWII, America and its allies had a responsibility to protect countries that were formerly under Japanese domination. North Korea attacked South Korea first, so stepping up to defend South Korea (and reverse North Korea’s initial conquest) was very clearly the correct thing to do.