Final answer:
America entered WWI not because it was directly attacked, but due to factors like Germany's submarine warfare, including the sinking of the Lusitania, and the interception of the Zimmerman Telegram, which shifted public opinion and strategic considerations.
Step-by-step explanation:
The entry of America into WWI was not a result of being directly attacked, but rather a combination of factors that eroded the United States' neutral stance. Despite President Woodrow Wilson's initial position to avoid international military conflicts, Germany's unrestricted submarine warfare, particularly the sinking of ships with American civilians such as the Lusitania, and the Zimmerman Telegram provoked public sentiment and led to increasing support for joining the Allies.
American isolationism was prevalent at the time, and there was considerable opposition to joining the war, especially among various immigrant groups and socialists. Inside the country, divisions were apparent, with conflict over whether to support Britain, with opposition from the Irish, and resistance to fighting against Germany, from the German immigrants. Significant figures and movements advocated for neutrality, but strategic and moral considerations eventually tipped the balance toward intervention.
The U.S. government also had to consider the impact on domestic affairs, the potential influence on the Allied morale, and the geopolitical landscape post-war. Ultimately, concerns about Germany potentially winning the war and the subsequent balance of power, as well as ideologies at odds with American interests, convinced the government that intervention was necessary despite the challenges of war preparation and the need to foster a wartime mentality among the American public.