You're right. I have come across old articles that report all the fun anti-war protests and that America had no business getting involved in WWII. Not much different that today, honestly.
We went to war in Europe due to Germany declaring war on us. Is that not what we are doing in the Middle East today? A Jihad was formally called for by many leaders against the U.S. either we fight them on our borders (Pearl Harbor/Twin Towers) or we take the fight directly to them. Its not about the oil people! its about American lives.