The scissors is a close-maneuvering technique, and as such, is really only useful when defending against guns or low-performance missiles. It was a major technique from World War I to the Korean War, but is much less common today. The introduction of high-angle missiles makes it much less effective, as the attacker can shoot even when the defender is not in front of them. Modern aircraft also make it difficult to use this technique as they maintain energy much better than earlier designs and the maneuvering limits are often the pilot's physical limitations, not the aircraft.