The first law, enacted February 9, 1909, prohibits the importation and use of opium for other than medicinal purposes. This was followed by an amended version in 1914. Another law enacted at the same time regulates the manufacture and smoking of opium within the United States. Laws passed in the 1920's pertain to taxes on persons who import, manufacture, and deal in opium; strategies for encouraging foreign governments to limit the production of narcotic drugs; prohibition of the importation of crude opium for the purpose of manufacturing heroin; the funding of drug enforcement efforts; and the establishment of narcotic farms for the confinement and treatment of persons convicted of drug offenses. Laws in the 1930's pertain to such issues as the creation of a Bureau of Narcotics within the Treasury Department; expenses for the United States participation in international drug conferences; the deportation of aliens convicted of drug offenses in the United States; an occupational excise tax on certain marijuana dealers; and the seizure and forfeiture of ships, vehicles, and aircraft used to transport narcotic drugs, firearms, and counterfeit coins, obligations, securities, and paraphernalia. Other laws in the decades through 1980 pertain to increased penalties for repeat drug offenders, expansion of treatment resources, prohibitions against other narcotic drugs deemed dangerous, and funding for drug abuse prevention and education.