This is an pane of 20.new World War I: Turning the Tide Forever stamps. This 2018 issuance honors the millions of Americans, both at home and abroad, who participated in World War I, the seminal conflict of the twentieth century. The United States, despite remaining neutral until 1917 and not engaging in major combat until 1918, helped end the four-year global conflict (1914-1918) and emerged from it as a major world power. The stamp art features a close-up of a member of the American Expeditionary Force holding the U.S. flag. Barbed wire can be seen in the background, as well as an airplane in flight and smoke rising up from the battlefield. The World War I: Turning the Tide stamp is being issued as a Forever stamp. This Forever stamp will always be equal in value to the current First-Class Mail one-ounce price.