Throughout the 2016 presidential election, Donald Trump’s attitude toward NATO has engendered significant consternation throughout both Europe and the U.S. foreign policy establishment. Although the president-elect has not explicitly advocated pulling out of the NATO, he has suggested that the United States should rethink its involvement since the United States continues to bear a disproportionate share of the defense burden within the alliance. The incoming administration could thus be poised to conduct the sort of “agonizing reappraisal” that John Foster Dulles threatened 63 years ago. Although a complete withdrawal from NATO would be unwise, the time to redefine the United States’ role in the alliance may have arrived.
Critics have attempted to undermine Trump’s intimation that he might refrain from defending NATO allies such as Estonia by suggesting that the United States is treaty-bound to do so. The day after Trump’s election, Jens Stoltenberg, NATO’s Secretary General, insisted that “NATO’s security guarantee is a treaty commitment…All allies have made a solemn commitment to defend each other. This is something absolutely unconditioned.” But that is only true to a certain extent. Article V of the North Atlantic Treaty stipulates that in the event of an attack against a NATO member state, each ally “will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.” The key phrase “as it deems necessary” gives the United States a great deal of latitude.
Were the North Atlantic Council to invoke Article V in response to a Russian incursion into Estonia, for instance, the United States could fulfill its treaty obligations in any number of ways. The Pentagon could certainly deploy the U.S. military to combat Russian forces directly. On the other hand, the United States could restrict its role to the provision of military equipment and logistical support to its European allies. To borrow a phrase from Franklin D. Roosevelt, the United States could serve as the great arsenal of NATO.