The post World War II “hub-and-spoke” alliance structure has served the United States and its allies well for the past six decades. Yet the transnational nature of current Asia-Pacific security challenges highlights the limitations of bilateral US ally relationships to handle regional security threats, traditional or not. Success demands that the US and its allies work with each other in a networked manner. This is not to suggest “NATO for Asia,” but it is time for an informal Alliance Caucus.