This work addresses a persistent empirical, theoretical, and policy gap in the study of foreign espionage against the United States: the absence of a unified, longitudinal, multi-adversary dataset of federal prosecutions suitable for systematic quantitative analysis. Although high-profile cases involving the People’s Republic of China, the Russian Federation, Iran, Cuba, and the Democratic People’s Republic of Korea have shaped public discourse and intelligence community priorities, scholars have lacked a population-level platform for testing claims about temporal trend, adversary differentiation, motivation, tradecraft, and sentencing. The purpose of the study is to construct and analyze the Foreign Espionage Apprehensions in the United States (FEAUS) dataset, covering 324 federal prosecutions from 2000 through 2026, and to use it to map systematic patterns across these dimensions. The methodology is a quantitative, non-experimental, longitudinal content analysis of indictments, plea agreements, sentencing memoranda, judicial opinions, Department of Justice press releases, and triangulating sources, with thirty-eight coded variables and inter-coder reliability validated through pilot kappa coding. Analyses include Mann–Kendall trend tests, chi-square tests of independence, one-way analyses of variance, ordinary least squares and logistic regression, and negative binomial count models. Findings document a strong post-2015 surge in case volume (Mann–Kendall τ = .874, p < .001), the dominance of cases attributed to the People’s Republic of China (49.4 percent of all cases), differentiated motivational signatures across adversaries (χ² = 38.46, p = .008) consistent with both MICE and RASCLS frameworks, convergence of human and cyber tradecraft (χ² = 45.39, p < .001), and significant sentencing variation across adversaries (F = 4.29, p < .001) and disposition types. Implications include adversary-differentiated counterintelligence prioritization, integration of human and cyber counterintelligence functions, evidence-based review of national-security statutory architecture, and proportionate research-security policy. The study contributes a replicable methodology and an empirical baseline for cumulative scholarship on foreign espionage in the United States.
Laszlo Pokorny (2026) studied this question.