Final answer:
The sinking of the Lusitania and other passenger ships during World War I changed the United States' response to the war and ultimately led to their involvement. These sinkings, coupled with Germany's intensified use of submarines, increased pressure on President Wilson to declare war.
Step-by-step explanation:
The sinking of the Lusitania and other passenger ships during World War I led to a significant shift in the United States' response to the war. Initially, most Americans viewed the sinking of the Lusitania as an act of unprovoked aggression by Germany, despite the presence of war materials on board. However, it was the sinking of subsequent ships and the loss of American lives that ultimately swayed public sentiment and led to the United States' declaration of war on Germany in April 1917.
The sinking of the Lusitania and other passenger ships highlighted the increasingly unrestricted submarine warfare tactics employed by Germany, which targeted any vessel suspected of carrying military supplies to Great Britain and France. These attacks put pressure on President Wilson to respond, and in February 1917, the sinking of the American merchant ship, the Laconia, and the subsequent sinking of four more American ships, further intensified calls for war against Germany.
The US response to the sinking of the Lusitania and other passenger ships can be seen as a turning point in American neutrality during World War I, leading to the eventual involvement of the United States in the war.