Aegis and SAMPSON are used as examples of systems optimized for threats approaching the defending ship or its nearby task group. A missile crossing an escort's position toward another ship can require a different intercept geometry. The defensive missile may enter a tail chase, using up fuel and increasing the risk of a miss. That affects the number of interceptors assigned to each target. A modern convoy could also occupy more sea room than the smaller task groups around which the defenses were planned.
Notable Point · 15:42-18:19
Why crossing missiles complicate convoy air defense
An escort defending another ship may have to chase a crossing missile rather than meet it head-on, while a dispersed convoy can exceed the area modern task-group defenses were built to cover.