This study examined private security deployments in critical national infrastructure (CNI) and the protection of foreign assets in Uganda, focusing on governance frameworks, operational performance, and strategic security risks. CNI comprised essential infrastructure and services whose disruption could affect national security, economic activity, public safety, and service delivery. Uganda’s expanding investments in energy, telecommunications, banking, transport, manufacturing, agribusiness, and public infrastructure had increased the number of strategically important assets requiring effective protection. Foreign assets, including multinational corporate facilities, diplomatic missions, telecommunications investments, financial institutions, oil and gas installations, and other foreign-owned properties, had similarly expanded alongside foreign direct investment. Against this background, the study assessed how PSO vetting, security-protocol compliance, intelligence sharing, and state coordination influenced threat detection, incident response, and protective security resilience. Descriptive statistics revealed significant gaps in CNI-specific security governance (means 2.94–3.47). All three governance dimensions were significantly correlated with CNI security effectiveness (r = 0.583–0.748, p < .001). The three dimensions collectively explained 65.2% of variance in CNI security effectiveness (R² = 0.652, F = 41.87, p < .001). SEM confirmed intelligence sharing and state coordination as the strongest total effect predictor (total β = 0.521), with CNI protocol compliance partially mediating this relationship. Recommendations address CNI security tiering legislation, intelligence coordination protocols, foreign asset security governance frameworks, and national CNI protection strategies.