when did the infantry start wearing the blue cord
Infantry Blue Cord A light-blue cord was created to be worn over the right shoulder of both officers and enlisted men. Also, light-blue plastic disks were issued to be placed behind the metal "crossed rifles" Infantry branch of service insignia disks as well as on the disc service cap insignia. The new enhancements were first worn by the 3rd US Infantry Regiment ("The Old Guard"). The light-blue cord and disks became standard for all Infantrymen in 1952.