I trench knife, primarily to conserve strategic metal resources. I trench knife for use in hand-to-hand fighting. I trench knife were marked "L.F.&C. 1918". The combat knife and the trench knife are examples of military fighting knives. In the ensuing bitter fighting, he killed two of the enemy with his trench knife. The U.S. Army adopted the M3 Trench Knife in 1943 as its standard combat knife. I trench knife is the German Army's "Nahkampfmesser" (close combat knife). As a class, these daggers, knives, and stilettos were given the title trench knife. I (with pictures of the "brass knuckle handle" trench knife dating back to 1917). Though not a true "trench knife" per se, the Fairbairn-Sykes was used for similar purposes.