This case study applies Coupling Geometry to the United Kingdom from the Glorious Revolution of 1688 to the present, testing seven predictions frozen from the coupling architecture against the historical and quantitative record; all seven are confirmed. The case produces a theoretical contribution — the combination longevity theorem: systems that combine elements from multiple longevity pathways achieve additive resilience, and the progressive loss of those elements produces accelerating vulnerability. The United Kingdom initially appeared to require a longevity pathway the programme’s register did not contain, approaching the framework’s own falsification condition on pathway exhaustiveness; investigation resolved the anomaly without a new mechanism. The UK is the historical record’s most successful combination of existing elements: institutional decoupling on the Venetian model (the 1688 settlement’s dispersal of power across Crown, Parliament, judiciary, central bank, civil service, and press), a permanent structural buffer and a positional material base on the Byzantine model (the Channel, and a maritime — later financial — trade network generating surplus from position rather than territory), and the element neither Venice nor Byzantium possessed in maturity: an expansion frontier at imperial scale, deferring distributional conflict for two centuries. Each element covered a different vulnerability, and the combination held the metropolitan core below the coupling threshold for three centuries — the 19th-century system scores C = 2.8 on the programme’s v3 rubric, among the lowest in the scored portfolio. The theorem’s converse organises the present: the frontier closed with decolonisation and its European substitute was abandoned in 2020; the positional base narrowed from diversified maritime trade to concentrated financial services; the buffer’s calibration range is being bypassed by threat categories that do not cross water; and the institutional decoupling is being actively reversed by executive concentration. The Involuntary Redistribution Theorem survives its two strongest apparent counterexamples — the 1945 settlement and decolonisation — both shown to be compelled rather than chosen. The analysis is post-hoc, its estimates analyst-dependent, and its prediction record carries the weight of internal-only pre-registration; adversarial examination by sceptical scholars is invited. Case Study XVI: The United States, 1991–Present – Case Study XVIII: The Late Bronze Age Collapse, c. 1200–1150 BCE
Philip Pepper (2026) studied this question.