Fleet air defence has several layers: aircraft and area-defence missiles at distance, point-defence weapons closer in, and close-in weapon systems as a final attempt. Medium-calibre guns formerly filled the point-defence role now associated with missiles. At terminal range, an incoming weapon may retain enough energy to reach the ship even after it has been hit. The preferred response is therefore to destroy the launching aircraft or incoming weapon earlier rather than rely on a last-ditch interception.
Notable Point · 2:53-3:50
Why fleet air defence must intercept before terminal range
Aircraft, area defence, point defence, and close-in weapons all serve the need to stop an attack before its final high-energy approach.