過去數十年來，外來直接投資出現大幅的成長，跨國企業在經濟全球化的過程中扮演益發重要的角色。然而，跨國企業在進行海外投資時多少會遭遇到來自地主國的政治風險，而導致經營損失或人員傷亡。國際關係學界中，商業自由主義者認為，商業活動與軍事衝突環境無法相容，軍事衝突將對跨國企業的海外投資造成負面影響。對此，本文從跨國企業的角度，分析軍事衝突在跨國企業進行政治風險評估中的地位，進而主張跨國企業的產業異質性將導致不同產業的跨國企業，對軍事衝突作出不同的認知與回應。因此，迥異於一般認為初級部門的跨國企業對軍事衝突最為敏感的看法，本文主張與投資地主國政經環境較緊密相關的製造業外資，更易受到地主國軍事衝突的影響並反映在其外資流入的減少上。本文利用美國對外直接投資的資料進行統計分析，結果顯示僅有製造業的外資流入與地主國的軍事衝突呈現具統計顯著性的負面相關，但軍事衝突對初級與三級產業的外資流入則無顯著影響。這些發現支持本文的假設，也相當程度地挑戰商業自由主義所持之商業活動與軍事衝突環境全然無法並存的論點。

Over the past decades, foreign direct investment (FDI) has grown significantly. The role of multinational corporations (MNCs) has become more important in terms of facilitating the process of economic globalization. Nevertheless, while conducting investment overseas, MNCs inevitably face the uncertainty of political risks, including militarized conflict, in host countries, which may deter MNCs' investment and lead to decrease in FDI inflow. Based on this logic, commercial liberalism argues that commerce cannot exist in a conflicting environment. MNCs and FDI tend to promote peace between nations since they deepen inter-state economic interdependence. By illustrating the role of militarized conflict in the concept of political risk, this paper investigates the preceding argument from MNCs' perspective and argues that the sectoral heterogeneity of MNCs leads to their different perceptions of and responses to militarized conflict. Different from a stereotype that MNCs in the primary sector tend to be more sensitive to militarized conflict than others in different sectors, this paper argues that FDI inflow in the manufacturing sector is more susceptive to militarized conflict, because this type of MNC is more likely to be affected by the changes of business environment in a host country. By utilizing U.S. sectoral FDI data from 1982 to 2004, this paper tests the preceding hypothesis. Statistical results support the argument and show that only MNCs in the manufacturing sector are negatively associated with militarized conflict.