In the immediate aftermath of September 11, 2001, transnational threats were revisited with a new urgency. The terrorist attacks on America's economic and military centers of power awakened the nation to the dangers posed by asymmetric and non-traditional threats. Transnational organized crime, in particular, is now recognized as one of the most dangerous and pervasive threats to national and international security. Profits from drug trafficking, smuggling, and other illegal activities fuel terrorism, violent conflict, and corruption around the world. Moreover, transnational crime is undermining military assistance programs, and peace operations in several regions. Law enforcement agencies have the lead role in combating organized crime, but current trends demand a close examination of how transnational crime is changing the national and international security environments and the strategic implications for the military. The growth of transnational criminal activity cannot be ignored and a greater support role by the military is vital and necessary. This paper will examine the nature of transnational organized crime, the principal criminal activities that contribute to violence and armed conflict; the impact of transnational crime on nation assistance programs and peace operations; and the strategic implications for the military.