The United States faces many foreign and domestic challenges, including the rise of a near-peer challenger and the relative decline of its closest allies. Its central policy dilemma is how to structure its foreign and national security policies toward its stated objective to maintain a leading role in international affairs under continuing fiscal constraints. This dissertation studies the strategic behavior of leading historical powers that faced rising challengers abroad and fiscal constraints at home. It accomplishes this through two case studies, one of Habsburg Spain and the other of Imperial Britain. In these case studies, the dissertation asks what these historical leading powers facing a similar policy problem tend to do, what drives them to take those actions, and how those choices affect their influence in international affairs. Each case study examines the respective power's rise to leadership, sources of power they primarily relied upon, where challenges came from, how they responded, how those policies worked out, and what constraints they faced in their decision-making. The dissertation concludes with significant takeaways from the case studies and discusses potential implications for American public policy.
Disclaimer: Research for the dissertation was completed as of April 2014 with selective updates through December 2022.