We all know the traditional narrative in International Relations of the state as a unitary act. Despite substantial volumes of work in the foreign policy analysis subdiscipline as well as in IR theory, the common shorthand in IR scholarship is to say ‘China’ did X or ‘Britain’ bombed Y. At least in the case of the United States, climate change is going to force scholars and analysts to seriously reconsider those assumptions.

In the wake of the Trump Administration’s (misguided) withdrawal of the United States from the Paris Agreement, a number of subnational actors have come forward pledging—in the international context—to act in contravention to the newly established US foreign policy toward climate change. Twelve states (plus Puerto Rico), representing more than a third of US national GDP, have signed on to the United States Climate Alliance with the express goal of pursuing substantial emissions reductions in line with US commitments under the Paris Agreement. Hundreds of mayors and leaders in higher education and business have signed an “Open letter to the international community and parties to the Paris Agreement” vowing to stay committed to the international climate change policy agenda. In short, subnational actors of all forms are openly and actively working to subvert the Trump Administration’s climate policy not just domestically, but internationally.

It is clear, then, that the current US foreign policy on climate change is not really the ‘US’ policy, but rather the policy of the Trump Administration and a subset of domestic actors who support it. Of course, this rump foreign policy is not entirely novel. Scholars of globalization have for years argued that the increasing interconnection of substate actors across state lines is fragmenting state power and, as a result, foreign policies. But the degree to which subnational actors in the United States are seeking to challenge the Trump Administration’s foreign policy internationally is striking. And the issue area is something quite different than traditional fare in discussions of globalization. The underlying physical and economic processes that drive Climate change are foundational to the modern political economy. When subnational actors seek to challenge the Trump Administration’s climate foreign policy, they are doing so in one of the most significant ways possible.

I can think of at least a few implications of this. It seems the Trump Administration has undermined its own ability to craft nationally coherent foreign policy. This may outlast the Trump Administration if subnational actors see foreign policy now as a legitimate area in which they can compete for international influence, particularly when the national government is deeply unpopular abroad. Conversely, foreign governments may also pay even more attention to subnational actors as an effective means of challenging American foreign policy. As much was suggested by the French Defense Minister when she is reported to have said with respect to climate change, “There are forces in the United States that we know we can rely upon, and these forces will ultimately prevail.”

Skeptics might of course argue that all of this is so much talk. Two points emerge to suggest that such a reading of events is wrong. First, the response by subnational actors demonstrates the extent to which the problems confronting modern nation-states lie across multiple policy vectors that span scale, and as such a multitude of actors are capable of taking meaningful action to address them (or not—the knife cuts both ways). Second, the deligitimation of Trump’s climate policy implicit in the contestation by subnational actors points to the importance of authority in international relations—a subject to which IR scholars pay relatively little attention. The recommitment by various states, most notably China, to Paris Agreement in the wake of Trump’s announced decision to withdraw of the US hints at the significance of authority: states sit atop an international hierarchy in substantial part because other states and societies voluntarily submit to what they see as legitimate leadership. By undermining the legitimacy upon which American international authority is based, the Trump Administration’s withdrawal from the Paris Agreement may have substantial repercussions for all aspects of US foreign policy