Even without the main dockyard, Singapore must control the strait and keep the fleet's northward route open. Permanent 15-inch batteries are cheaper than rotating battleships out of the Home and Mediterranean Fleets, and a token detachment could be strong enough to invite a preemptive strike yet too weak to change the campaign. Sydney then needs heavy guns of its own, including 15-inch and 9.2-inch weapons, because the new imperial base raises Australian sites on an enemy target list. A Gurkha brigade or division is one possible Sydney garrison, and Australia would also need to fund more fighters. The scenario therefore duplicates costly protection rather than transferring it. Fixed fortifications can preserve mobile fleet strength when geography forces several strategic nodes.
Notable Point · 1:02:38-1:05:53
Fixed guns preserve battleships for the mobile fleet
Heavy batteries at Singapore are cheaper than rotating battleships forward, while Sydney would need comparable weapons once it became an imperial target.