Based on "how we entered world war i," which detail explains why the sinking of the lusitania led the united states to enter world war i?

Hi. I noticed that there are no choices added in your post. Just in case there is none, then I'll go ahead and answer your question.

Based on "How we entered World War I," the detail that explains why the sinking of the Lusitania led the United States to enter World War I because there were about one hundred twenty-four passengers who died and a total of one thousand one hundred ninety-five passengers killed.

Imperialism was a cause because building an empire needs manpower such as an army and a navy to conquer and keep the land that they colonised. The alliances system meant that a local conflict could easily result into an intimidating global one. ... This leads to Imperialism.