Articles

The defining question about global order for this generation is whether China and the United States can escape Thucydides’s Trap. The Greek historian’s metaphor reminds us of the attendant dangers when a rising power rivals a ruling power—as Athens challenged Sparta in ancient Greece, or as Germany did Britain a century ago. Most such contests have ended badly, often for both nations, a team of mine at the Harvard Belfer Center for Science and International Affairs has concluded after analyzing the historical record. In 12 of 16 cases over the past 500 years, the result was war. When the parties avoided war, it required huge, painful adjustments in attitudes and actions on the part not just of the challenger but also the challenged.

American Secretaries of State Project honoree Henry A. Kissinger looks back on George C. Marshall's groundbreaking 1947 Harvard Commencement speech and its enduring importance for American foreign policy.

States have long worried that their dependence on oil gives producers a means of coercion. The oil market, however, is far larger and more integrated than it used to be. The potential for coercion differs across a series of distinct market segments. In this varied market, the United States remains the dominant force.

Chinese President Xi Jinping addresses China’s new concept of nuclear security with four “equal emphasis” at the third Nuclear Security Summit, and makes four commitments to strengthen nuclear security in the future. To convert President Xi’s political commitments into practical, sustainable reality, China should take further steps to install a complete, reliable, and effective security system to ensure that all its nuclear materials and nuclear facilities are effectively protected against the full spectrum of plausible terrorist and criminal threats. This paper suggests the following measures be taken to improve China’s existing nuclear security system, including updating and clarifying the requirements for a national level DBT; updating and enforcing existing regulations; further promoting nuclear security culture; balancing the costs of nuclear security, and further strengthening international cooperation on nuclear security.

Senior Fellow William H. Tobey evaluates the effectiveness of President Obama's policies to stem the threats of nuclear proliferation and terrorism.

U.S. scholars and policymakers commonly worry that a lack of "energy security" hurts U.S. national security, yet few have analyzed the links between states' energy requirements and the probability of military conflict. An investigation of these links identifies threats to U.S. national security flowing from other countries' consumption of oil, rather than just U.S. consumption. Furthermore, while many of the security threats associated with Persian Gulf oil have decreased, new oil-driven dangers are emerging in Northeast Asia.

Many experts consider nuclear terrorism the single greatest threat to U.S. security. The fear that a state might transfer nuclear materials to terrorists was a core justification for the invasion of Iraq in 2003 and, more recently, for a strike against Iran’s nuclear program. The logical basis for this concern is sound: if a state could orchestrate an anonymous nuclear terror attack, it could destroy an enemy yet avoid retaliation. But how likely is it that the perpetrators of nuclear terrorism could remain anonymous? Data culled from a decade of terrorist incidents reveal that attribution is very likely after high-casualty terror attacks. Attribution rates are even higher for attacks on the U.S. homeland or the territory of a major U.S. ally—97 percent for incidents in which ten or more people were killed. Moreover, tracing a terrorist group that used a nuclear weapon to its state sponsor would not be difficult, because few countries sponsor terror; few terror groups have multiple sponsors; and only one country that sponsors terrorism, Pakistan, has nuclear weapons or enough material to manufacture them. If leaders understand these facts, they will be as reluctant to give weapons to terrorists as they are to use them directly; both actions would invite devastating retaliation.

A common argument among scholars and policymakers is that America’s military preeminence and deep international engagement yield significant economic benefits to the United States and the rest of the world. Ostensibly, military primacy, beyond reducing security tensions, also encourages economic returns through a variety of loosely articulated causal mechanisms. A deeper analytical look reveals the causal pathways through which military primacy is most likely to yield economic returns: geoeconomic favoritism, whereby the military hegemon attracts private capital in return for providing the greatest security and safety to investors; direct geopolitical favoritism, according to which sovereign states, in return for living under the security umbrella of the military superpower, voluntarily transfer resources to help subsidize the costs of hegemony; and the public goods benefits that flow from hegemonic stability. A closer investigation of these causal mechanisms reveals little evidence that military primacy attracts private capital. The evidence for geopolitical favoritism seems more robust during periods of bipolarity than unipolarity. The evidence for public goods benefits is strongest, but military predominance plays only a supporting role in that logic. While further research is needed, the aggregate evidence suggests that the economic benefits of military hegemony have been exaggerated in policy circles. These findings have significant implications for theoretical debates about the fungibility of military power and should be considered when assessing U.S. fiscal options and grand strategy for the next decade.

In 1985, researchers at the Harvard Kennedy School published a book called “Hawks, Doves, and Owls,” and gave it an ambitious subtitle: “An Agenda for Avoiding Nuclear War.” Those scholars gathered again at the School on Monday (May 16) for a seminar on the current challenges in avoiding nuclear war — and to marvel at just how drastically the nuclear threat has morphed in the two decades since the Cold War ended and the Soviet Union collapsed.