With a little over a year before the withdrawal of troops from Afghanistan, the United States has attempted to navigate complicated global crises without being drawn into additional conflict. Without a doubt the current crises in North Korea and Syria have tested that resolve. While the case for support or intervention can be debated within Congress and the corridors of the West Wing, one potential document has the legal authority to bind the United States to action without debate, public approval, or a congressional vote. Article V of the North Atlantic Treaty obliges the United States and its signatories (twenty-eight member countries in total) to collective defense in the event one of the member states is attacked. Similar to the alliance system that helped expand the Great War, this agreement continues to increase in members with Albania and Croatia joining in 2009, adding to the increased potential for errant state actors.

The Atlantic has a good article out right now on mayoral participation in global diplomacy. According to the authors, the practice is increasingly common and ambitious. Mayors of large cities have taken on issues ranging from global warming to nuclear disarmament, to economic growth and terrorism. These efforts are also becoming more institutionalized. The mayor of New York, for example, has a “Mayor’s Office for International Affairs,” and Europe has an “EU-China Mayors’ Forum” that promotes relations between European and Chinese municipal authorities. The authors use the term “diplomacity” to refer to the “expanding propensity of cities to develop the necessary mechanisms to autonomously navigate foreign relations on their own.”

These developments strike me as interesting for a couple of reasons. First, they form half of a two-dimensional assault on a classical model of international relations, which identifies heads of state and their agents as the critical channels for official communication. Diplomacity amounts to a vertical assault on that model because it reflects a dispersion of diplomatic activity among national and local authorities. Communication by national officials other than heads of state—such as legislators—forms the other half: a horizontal assault in the form of a dispersion of diplomatic acts among component parts of national governments. Neither of these is new, but both have intensified under globalization. The result is an entirely different picture of international relations. If diplomacy under the classical model was centralized and tidy, the contemporary counterpart is decentralized and cluttered with a broad range of actors. This has both benefits and disadvantages. States and localities, for example, will often possess unique perspectives on international problems and unique capacity to develop solutions, but the proliferation of voices may also complicate the management of inter-state relations.