as the timeframe of the deployment of the First Marine Aviation Force in France during July 1918 until roughly 1922, the USMC's aviation units added an American eagle atop the roundel and a fouled anchor superimposed behind the roundel, mimicking the Eagle, Globe, and Anchor emblem on the fuselage sides in the manner of a unit insignia. Post-WW I and interwar period In May 1917 the US adopted a red circle-centered white star in a dark blue circular field for all United States military aircraft. In August 1919, following the Armistice that ended World War I, the colors were adjusted to the current standards and the proportions were adjusted slightly so that the centre red circle was reduced slightly from being 1/3 of the diameter of the blue circular field, to being bound by the edges of an imaginary regular pentagon connecting the inner points of the star. American entry into World War II The US Army Air Corps began painting its roundel on only the top of the left wing and only the bottom of the right wing February 26, 1941, intended to help facilitate recognition of friend and foe if the United States became embroiled in the spreading conflict. The other reason was to “eliminate a balanced target” by presenting a somewhat asymmetrical effect — if you see two white stars (i.e., one on each wing), it is easier to aim your guns between them. The US Navy resisted this change and reverted to the roundel on each wing early in the war January 5, 1942. However, the US Navy finally adopted the asymmetrical single wing insignia February 1, 1943. In the months after Pearl Harbor - following the late-June 1941 conversion of the USAAC into the United States Army Air Forces - it was thought that the central red dot could be mistaken for a Japanese Hinomaru, from a distance and in May 1942 it was eliminated. On aircraft in service they were painted over with white. During November 1942, US forces participated in the Torch landings and for this a chrome yellow ring (of unspecified thickness) was temporarily added to the outside of the roundel to reduce incidents of Americans shooting down unfamiliar British aircraft, which could themselves be distinguished by a similar yellow outline on the RAF's "Type C.1" fuselage roundels of the time. None of these solutions was entirely satisfactory as friendly fire incidents