During the difficult years that preceded the British handover of Hong Kong to China, the Chinese government's intense antipathy to opium and the still fresh memories of the evil that 18th century buccaneering Britain had inflicted on China and Hong Kong added an extra emotional charge to what, anyway, was a most complicated transition. Without opium there would have been no Hong Kong. The British only acquired it because of the Opium Wars, and the city's early economic success was built on the opium trade.
It was the British who fed the Chinese propensity for opium. Historians point out that the Chinese would have found it elsewhere, even grown some of it themselves. But the truth is the Indian-grown opium was the brand the Chinese smokers savoured and the British East India Company marketed it with commercial élan.
Today the Chinese authorities regard opium as a singularly bad thing. But in Hong Kong there is a public debate, shades of grey, layers of complexity, both historically and currently. The study of opium becomes as complicated as an addict's dreams and the solutions to abuse as tortuous as cold turkey.
It was the Communist revolution that expunged opium in mainland China. Mao Zedong with his political apparatus that reached into every hamlet and home was able, as he repressed so many attributes of human nature both good and bad, to lay the beast low.
It was a mixture of carrot and stick. Addicts were not condemned but offered medical help and rehabilitation. But those who were uncooperative were sent to labour camps or imprisoned. Dealers were summarily executed, often without trial.
China was clean for 40 years, until the demise of Mao. Gradually opium has returned. Now China is one of the world's most important opium growers. Although China still regularly executes drug traffickers, demand in its freewheeling economic society finds willing suppliers prepared to take the risk.
Government attitudes in China have not changed. But the black market is a match for government, as it is almost everywhere. The black market grows by the decade and repression, unless it is totally totalitarian, leaves enough loopholes for the determined to wriggle through.
The zeal to repress in most countries of the world has become quite counterproductive, building up the wealth and criminal reach of the drug barons who have become so powerful that they often have a political influence that distorts, even threatens, good governance. By all accounts their influence is growing and the various types of control - from Europe's tolerance of soft drugs but toughness on hard, to China's rigorous policy on executing dealers - are clearly not working. At least in Hong Kong there is a reasonably informed and intelligent debate. In China, as in many parts of America and Europe, debate is barely tolerated.
Hard drugs may be forbidden today in Britain and Hong Kong, but at least, unlike most states in the U.S., there is no longer any debate about their medicinal uses. This is why it is probably best to die from some painful cancer in a British hospice, as my mother did. Britain is one of the few countries to allow the use of heroin as a pain suppressive, the strongest painkiller of them all.
The truth is that neither China with its millennia of centralized government nor the U.S. with its technological prowess is a match for the drug traders. The tough policies of China, Malaysia, Singapore and Thailand who execute minor traffickers have rarely touched the big barons.
We either do what Mao did - allow our governments to be simply totalitarian on this issue and implement a scorched earth policy - or we legalize opium and other drugs to break the back of the underworld trade. We then deal with addiction by educational and medical means. It is the present and almost universal in-between that is so unsatisfactory and so dangerous.
On Tuesday, Vicente Fox, former president of drug-ridden Mexico, surprised the country by saying it was necessary to legalize drugs in Mexico. He argued this would pull the rug from under the murderous drug barons who can only make their huge profits when drugs are prohibited. This is how it should be - in China, the U.S., Latin America, Nigeria and Europe. No other policy will defeat the drug mafias.
Jonathan Power is an international affairs writer.