Yes, Teribus, I'm aware of those 2 theories as well as the theory about explosives being aboard. They're all definitely worth considering. At any rate, it appears that the ship was carrying war materials, therefore the Germans felt that it was a legitimate target. The German captain of the U-boat was reportedly pretty horrified as he watched the unexpected rapidity of the sinking, the spilling of lifeboats, and the deaths of so many panicked passengers. War, as always, is a miserable business. People do it because they think they must...under the circumstances. In so doing, they often lose a very big part of their soul in the process.

As you point out, Les, there was a very big time lag between the Lusitania's sinking and the US entry into the war, so I hardly think it was the decisive reason behind the USA decision to go to war.