Singapore arms its OPVs for wartime control of the strait

Securing the Singapore Strait protects Singapore's economic access to the wider world. Keeping that choke point available to allies and denying it to opponents also gives larger partners a reason to help defend the country. The Independence-class patrol ships form part of that local force and can defend themselves within limits. Friendly air support and other assistance are hoped for, without being treated as guaranteed. Because Singapore expects to need these OPVs in war and cannot assume time or facilities for a refit, their existing armament reflects that wartime role.