What legal justification does the United States need in order to defend Taiwan, and why does it matter? The question strikes at the heart of many of the priorities of the incoming Biden administration, which will be faced with immediate questions about how to deal with China on the one hand, and how to manage the balance between executive and congressional war powers on the other.
American presidents have worried about the credibility of threats since the beginning of the Nuclear Age. The question of whether Congress would authorize a U.S. response to Soviet aggression in Europe bedeviled policymakers, who struggled to make commitments to Europe look automatic even when they were contingent upon Congressional action. NATO’s article five, for example, includes sufficient wiggle room to allow the U.S. to avoid war in spite of its commitment. This uncertainty is regarded as deadly for deterrence theory, which relies upon the clarity and credibility of alliance commitments to prevent war. In its classic formulation, if the Soviets were uncertain that the U.S. would fulfill its alliance commitments, they might be tempted to attack Western Europe.
A curious version of the problem developed during the Obama administration, when President Obama initially sought Congressional authorization for military action against Syria in response to chemical weapons attacks. Congress declined to give such authorization, resulting in a murky situation that largely left the decision to Obama. At the time, advocates of a strong executive hand in foreign policy decried Obama’s decision, arguing that it added an additional veto point in U.S. foreign policy decision-making and thus reduced U.S. credibility.
Patrick Hulme, a graduate student at the University of California-San Diego who specializes in Congressional-Executive relations, points out that the general problem of credibility is complicated by the unique relationships between Washington, Taipei, and Beijing. Clear Congressional instruction to the executive might violate the policy of strategic ambiguity with respect to Taiwan’s status. Any motion strong enough to send a credible message to China might be strong enough to trigger risky moves by either Beijing or Taipei.
Of course, the nature of the strategic relationship between the United States and China has not, until recently, been balanced on the same kind of hair’s-breadth precipice that prevailed during the Cold War. This means that if conflict looms between Taiwan and China at some point in the not-too-distant future, Congress would likely have time to contribute legislation that would free the hand of the executive branch. However, Hulme notes that the increasing military power of China has tended to narrow the window in which Congress could act, putting a premium on pre-emptive legislative action.
With these complications in mind, the problem nevertheless seems quite similar to credibility issues that the United States has had to manage since the beginning of the Cold War. However, recent developments in Congressional thinking on war powers complicates the question of how willing Congress will be to write the president a blank check on Taiwan. Critics of the Trump administration on both the left and the right have argued that the executive branch has taken excessive control over war powers, and needs to be reined in by Congress. This view has been especially pronounced among President-elect Biden’s allies on the left. Thus, the prospect of Biden asking Congress for wide ranging strategic authorizations in the Pacific, and of Congress acquiescing in that request, is perhaps a touch more of a tricky prospect than usual.
To be sure, in the event of a Chinese attack against Taiwan, Biden has sufficient executive powers to react without waiting for Congressional action. Moreover, there is little reason to believe that Beijing takes the prospect of Congressional obstruction very seriously. The hope that Congress might prevent a U.S. president from responding to an attack upon Taiwan would be a thin reed upon which to risk a devastating war. Nevertheless, Taipei and Beijing should both watch the evolution of Congressional relations with the Biden administration closely.