During world war i, the main goal of the us government agency that created war posters was
to increase public support for the war. to convince the soldiers in europe to fight. to get president wilson reelected. to take people’s minds off the war.

Really the advertising, or more correctly propoganda, was designed to increase public support for the war in the USA. Posters were designed to stir up a sense of patriotism and duty in the American people that would iead to them either signing up to fight or supporting the war effort in another way.