American diplomacy hasn't vanished—it just changed addresses. As the federal government pivots toward isolationism under the second Trump Administration, the machinery of international engagement hasn't ground to a halt so much as decentralized, flowing outward from Washington to Sacramento, Austin, Boston, and beyond.
The concept isn't entirely new. American federalism has always contained within it the seeds of diplomatic multiplicity. The Constitution may reserve formal treaty-making for the federal government, but it hasn't prevented governors from boarding planes to Beijing or mayors from signing climate accords with European counterparts. What is new is the scale and stakes of this subnational diplomacy—and the void it now attempts to fill.
The first Trump administration provided a dress rehearsal for this distributed diplomacy. When the White House announced its intention to withdraw from the Paris Climate Agreement, a coalition of states, cities, and businesses materialized almost overnight, pledging to honor America's climate commitments regardless of federal policy. Governors appeared at international climate conferences, standing in for absent federal representatives. Mayors established direct channels with foreign counterparts, bypassing State Department intermediaries. Universities and businesses forged international partnerships independent of federal blessing.
The second Trump era offers an opportunity not just to react but to build—to transform these scattered diplomatic impulses into something more coherent and durable. The constitutional constraints remain firm: no state can negotiate a formal treaty or claim to represent the United States. But within these boundaries lies considerable room for maneuver.
Climate action presents the clearest opening, with state-level carbon markets and emission requirements maintaining momentum regardless of federal regulation. Similarly, state trade offices that once simply facilitated business connections now serve as crucial maintenance crews for international commercial relationships threatened by federal protectionism. Universities and cultural institutions have evolved into diplomatic outposts, developing workarounds to federal visa restrictions through satellite campuses and digital exchanges, while tourism boards preserve people-to-people ties during periods of federal disengagement.
The architecture of American subnational diplomacy continues to develop. Sister city relationships—those quaint relics of Cold War cultural exchange—have transformed into substantive economic and policy cooperation channels. Consulates in major American cities, once primarily service providers for their nationals, now function as bridges between foreign governments and American states and municipalities.
None of this comes without complication. The Constitution casts a long shadow over subnational foreign policy, and the line between permissible international engagement and unconstitutional usurpation of federal authority remains blurry. Coordination problems abound when multiple states engage with the same international partners, potentially with conflicting priorities. For foreign counterparts, questions of credibility loom large. Can agreements with states survive changes in local leadership? Do commitments from California carry weight if contradicted by federal policy?
Federal pushback presents another obstacle. Past administrations haven't hesitated to threaten funding cuts or legal challenges against states and cities whose international engagements contradicted federal priorities. These pressures will only intensify as subnational diplomacy expands into domains traditionally reserved for Washington.
For citizens concerned about America's place in the world, subnational diplomacy offers avenues for engagement beyond federal channels. Participating in exchange programs, supporting internationally engaged businesses, and advocating for state and local international initiatives all contribute to maintaining America's global connections during periods of federal withdrawal.
This isn't resistance to federal policy so much as insurance against its consequences—a recognition that America's international relationships are too valuable to be wholly dependent on presidential administrations' philosophical oscillations.
One might reasonably ask whether this distributed diplomacy can adequately substitute for traditional federal engagement. The answer is clearly no—not completely. No governor can deploy military assets or negotiate binding treaties. No mayor can establish an immigration policy or impose tariffs. The tools of subnational diplomacy remain limited.
Yet complete substitution isn't the point. In a world where challenges from climate change to pandemic response transcend national boundaries—and where solutions often emerge locally—perhaps American foreign policy was destined for decentralization. Perhaps the diplomatic monopoly long claimed by the federal government was already becoming anachronistic before the current administration hastened its erosion.
The United States has always contained multitudes. Now, increasingly, so does its diplomacy. In the absence of coherent federal leadership, perhaps it’s not subnational diplomacy that’s the aberration—but the notion that one president could ever speak for America alone.