In this report, the authors evaluate the factors that drive regional and third-party responses to territorial revision attempts. They analyze five case studies that span peaceful cession, resistance with little international support, and resistance with significant international support. Each case study occupies a different place in this array, with the case of Hong Kong featuring a fully peaceful cession and the Soviet invasion of Czechoslovakia seeing some very limited local resistance. The Japanese invasion of Manchuria saw full-scale local resistance with no international support. At first, the Iraqi invasion of Kuwait met significant Kuwaiti resistance with no immediate international support, followed by a full-scale coalition response. Last, in the case of the Crimean War, the conflict was internationalized from the very beginning. Using quantitative and qualitative methods, the authors found that third-party states take into account a variety of factors involved in the territorial revision when determining their alignment decisions in its aftermath. These factors include fears of successive revision attempts, continued credible involvement from another outside power, legitimacy according to international and regional organizations, economic links between relevant parties, and the treatment of the population after a territorial takeover.

The United States, according to official U.S. national security statements and an avalanche of commentary since about 2016, is engaged in a long-term strategic rivalry with China and a lesser — but still critical — rivalry for influence with Russia. Many U.S. strategy documents refer to the concept of strategic competition, but the core idea — and increasingly the reality — of these relationships matches the classic historical concept of a great power rivalry. These rivalries, especially with China, promise to define U.S. foreign policy and national security challenges for decades. Yet most assessments of these rivalries tend to ignore the critical question of outcomes. This report is part of a larger project on the societal sources of national dynamism and competitive advantage. This research aims to identify historical modes of strategic success and failure in great power rivalries that offer lessons for the United States. The authors define categories of success and failure (in terms of such variables as control over territory, relative power, victory or defeat in war, international legitimacy, and social stability) and present detailed case studies on specific historical examples that are associated with success and failure. They also discuss the implications of the typologies of both kinds of outcomes for the rivalry with China.