Air-defence supplier diversity and fleet demand

What air-defence system should all Western navies adopt across their ship types?

No universal system is recommended. The preference is for competing options, supported by enough purchasing demand to sustain them.

Universal adoption of one missile system is criticised for simplifying an opponent's preparations and removing supplier competition. A favourable assessment of Standard Missile therefore accompanies a preference for retaining alternatives. The same reasoning applies to 76 mm, 57 mm and 40 mm guns. Competing systems need enough countries buying them and enough ships receiving them. Below a certain demand level, competing production lines would lack an economic basis.