Today's complex, chaotic, and interconnected world has forced us to rethink some of our fundamental assumptions about the nature of leadership, especially when it comes to leading whole-of-government or even whole-of-nation efforts. This is especially the case in the U.S. national security enterprise (hereafter referred to as the NSE or enterprise) where a complex, diverse constellation of military and civilian agencies must wield both hard and soft power on behalf of the United States. For various reasons, that enterprise has become our nation's first responder when it comes to almost any challenge, from traditional military operations to a myriad of nonmilitary ones, to include disaster and pandemic relief and humanitarian assistance (the Ebola crisis comes to mind), post-conflict reconstruction, and even nation-building. Irrespective of the challenge, our nation's political leaders look to senior officers-particularly but not exclusively those in uniform-who are in, and/or who have been developed by our NSE to lead the way.However, are they prepared for what we ask of them? As former U.S. Coast Guard Commandant, Admiral Thad Allen and others (including myself) have argued, almost everything of any consequence that government does today is collaboratively co-produced by a complex collection of public and private entities, from other agencies and levels of government, to nongovernmental organizations (NGOs) and even other countries, and international bodies.1 This is becoming the new normal for national leaders-whether they are elected, or in the case of senior career military and civilian officials, appointed or selected-and it has made their job exponentially more difficult. From the short-term dramas of pandemics, hurricanes, ecological disasters, and lone wolf terrorist attacks to the decades-long challenges of homeland security, energy independence, the health of our veterans and, at the extreme, great power competition and conflict-virtually everything government does requires the concerted efforts of complex networks that are comprised of multiple actors and organizations.In this regard, there is a realization among senior government leaders, both military and civilian, that the national security challenges they face can no longer be addressed by individual agencies or commands, each narrowly (even myopically) focused on its own specialized authorities and responsibilities. Rather, as those challenges become even more complex and interdependent, leaders at all levels-all with potentially overlapping jurisdictions and diverse areas of expertise-are required to collaborate with one another towards some common mission outcome. Thus, NSE leaders must have the meta-leadership skills to reach beyond their immediate organizations and mobilize a network of interdependent actors to achieve a shared mission and in so doing, achieve outcomes that are greater than the sum of their individual parts.2A New Kind of NSEFor purposes of this paper, NSE is defined in two ways. First, in concept, it represents all of the various departments and agencies, mostly though not exclusively federal, that have some responsibility for the U.S. national and homeland security missions broadly defined. This includes the usual suspects like the Defense Department (DOD) and the elements of the Intelligence Community (IC), but it also includes parts of the Departments of Energy, State, Justice, and Commerce, as well as more specialized agencies and departmental subcomponents like the United States Agency for International Development, the Federal Bureau of Investigation (FBI), and the National Oceanic and Administrative Administration.Not every element of that constellation of organizations will be relevant to a particular circumstance-indeed, that is part of the leadership challenge-so the second definition is more situational. In that context, the NSE is that operational subset of those institutional entities that may be necessary to accomplish a specific national or international mission sanctioned by the United States as relevant to its national security. …