In July 2011, President Barack Obama promulgated the Strategy to Combat Transnational Organized Crime. In the letter presenting the strategy, President Obama stated that the expanding size, scope, and influence of transnational organized crime and its impact on U.S. and international security and governance represent one of the most significant challenges of the 21st century. The President noted that criminal networks were not only expanding their operations but also diversifying their activities, resulting in a convergence of transnational threats that has evolved to become more complex, volatile, and destabilizing.These networks, Obama stated, also threaten U.S. interests by forging alliances with corrupt elements of national governments and using the power and influence of those governments to further their criminal activities. This report will show that transnational criminal networks (TCNs) are a critical destabilizing factor in the global security environment and an emerging threat to U.S. national interests. To effectively address these complex and adaptive threats, U.S. whole-of-government as well as international comprehensive approaches will be required. This report will also argue that combating transnational criminal organizations is a legitimate and important role for the U.S. Army, one in which its current efforts could be significantly expanded.