How to Hide an Empire: A History of the Greater United States

by Daniel Immerwahr

The Guano Islands Act, the Supreme Court’s ruling, and President Harrison’s backing of that ruling collectively established that the borders of the United States needn’t be confined to the continent. In 1889–90, when the Navassa controversy was in the news, this was a minor concern. But in the decades to come, it would be the foundation for the United States’ entire overseas empire. The second legacy was strategic. The same features that made the islands attractive rookeries for seabirds made them, decades later, desirable sites for airfields. The pointillist empire that the United States built after the Second World War would rely in part on those nineteenth-century guano claims. The third and most immediate legacy was agricultural. In all, speculators scraped some four hundred thousand tons of rock guano off of U.S. appurtenances. That fell short of speculators’ wildest hopes, but it was nevertheless a significant haul.