This study explores the origins and consequences of a unique, secret, French–American collaboration to prospect for uranium in 1950s Morocco. This collaboration permitted mediation between the United States and France. The appearance of France in an American-supported project for raw nuclear materials signalled American willingness to accept a new nuclear global order in which the French assumed a new, higher position as regional nuclear ally as opposed to suspicious rival. This collaboration also permitted France and the United States to agree tacitly to the same geopolitical status for the French Moroccan Protectorate, a status under dispute both in Morocco and outside it. The secret scientific effort reassured the French that, whatever the Americans might say publicly, they stood behind the maintenance of French hegemony in the centuries-old kingdom. But Moroccan independence proved impossible to deny. With its foreseeable arrival, the collaboration went from seductive to dangerous, and the priority of American and French geologists shifted from finding a major uranium lode to making sure that nothing was readily available to whatever post-independence interests might prove most powerful. Ultimately, the Kingdom of Morocco took a page out of the French book, using uranium exploration to assert sovereignty over a different disputed territory, its de facto colony of the Western Sahara.