Trace how the international drug-control regime evolved from the Shanghai Commission (1909) to the Geneva Convention (1925). How far did colonial revenue interests weaken it?

Between 1909 and 1925, international drug control grew from non-binding recommendations into a treaty system with its own supervisory body [1]. Colonial treasuries, however, made sure the regime regulated the opium trade without ending it.

Evolution of the regime: 1909–1925

Shanghai 1909 → Hague 1912 → Versailles 1919–20 → Geneva 1925
 (recommend)      (bind)      (universalise)       (supervise)

Fig.: Stages in the regime's growth

• Shanghai Opium Commission (1909): the first multilateral meeting on narcotics. It issued recommendations only, but it prepared the ground for a treaty [1].
• Hague International Opium Convention (1912): the first binding drug treaty. It covered shipments of narcotic drugs and came into force in 1915 [2].
• Versailles (1919–20): World War I had stalled ratification. Ratifying the peace treaties now also meant ratifying the Hague Convention, which widened its reach [1].
• Geneva Convention (1925): introduced licensing and recording of all transactions, made statistical returns compulsory and created the Permanent Central Opium Board [2]. It brought "Indian hemp" under control [1] and set a 15-year path to suppress prepared opium [3].

How far colonial revenue weakened it: significantly, but not fully

• Production untouched: the colonial powers refused to cut opium cultivation, so the US and China walked out of Geneva [3].
• India as supplier: British India produced about 12% of world opium, making it the second-largest producer, and it announced only a gradual cut in non-medical exports in 1926 [3].
• The state as dealer: in 1926 a Colonial Office report on Malaya praised government Chandu (smoking-opium) saloons as a "successful experiment". As evidence it cited 14,00,000 dollars of extra revenue, drawn from migrant workers on tin and rubber estates [4].
• Slow implementation: the Geneva Convention came into force only in 1928, and the Board began work in 1929. In the meantime, large quantities of drugs passed into illicit traffic [2].
• Limits to the damage: even so, licensing, statistics and a supervisory board became lasting institutions. They lead directly to the 1961 Single Convention and the INCB [2].

Overall, the regime grew stronger in law between 1909 and 1925 while colonial finance held back its impact in practice. Revenue interests turned a planned prohibition into gradual regulation of trade, but they could not stop its institutions from deepening. The lasting lesson, relevant to SDG 3.5 today, is that drug control works only when the authority that regulates a harmful product does not also profit from selling it.