The Lusitania was most likely carrying a large quantity of contraband munitions, which is why the Germans sank it, and they had issued warnings of the danger to Americans prior to its sailing. It may have been the detonation of those munitions which caused the ship to sink so rapidly.

I very much doubt that the USA genuinely entered WWI because of the sinking of the Lusitania, but rather that the incident was handily used to help shape public opinion around about the time the politicians had decided that it was expedient to get America involved...for various large financial and strategic reasons.

The usual stuff, in other words. Realpolitik. Nothing is as great an excuse for killing a few hundred thousand more people as the loss of a much smaller number of people on a ship. It's been done again and again. It's something the ordinary guy in the street can understand...and get danged upset about. Governments deal in colder calculations than that.

However, Kendall, I agree that Wilson had some good points, as politicians go.