The four S's of a cruiser

The four S's provide a practical way to judge whether another ship type can perform cruiser work. Scouting and screening describe the wartime functions, while scurrying around the world and socialising capture visible peacetime presence and diplomacy. Submarines can contribute to the first pair, but their stealth makes them poor tools for the second. The framework helps explain why a useful combat platform cannot automatically replace a cruiser in every role.