Final answer:
The American public pressured the government to declare war through protests, propaganda, public opinion, and the perception of threats to national security.
Step-by-step explanation:
The American public pressured the government to declare war through a combination of factors and events. One of the main ways the American public exerted pressure was through protests and demonstrations, such as the anti-war protests at the US Capitol in April 1917. Additionally, the Committee on Public Information utilized propaganda and advertising principles to influence public opinion and garner support for the war effort.
Furthermore, factors such as ongoing attacks on American ships and the fear of Japan's growing power in the Pacific played a role in mobilizing public opinion in favor of war, as seen with the support for US entry into World War II following the attack on Pearl Harbor.
In summary, the American public pressured the government to declare war through protests, propaganda, public opinion, and the perception of threats to national security.