I strongly admire the determination that many Czechs and Slovaks feel to rejoin their countries to the West. Capitalism and democracy are incomparably good. Their fruits are a continual amazement. Simply put, Westernisers are the friends of humanity, their enemies its enemies.

So often, though, they lack discrimination. They tend to jumble together what is essential to Western civilisation with much that is accidental or even hostile to it: they take the baby, but cannot leave the bathwater behind. Thus the Japanese gave themselves an industrial revolution - and also Victorian prudery. The Indians gave themselves Westminster- style democracy - and also British socialism.

The same is happening here. Along with sound money and the rule of law, the Czechs have given themselves a "War against Drugs". I read (August 18-24) of the disquiet felt at police inability to put down drug dealing in Wenceslas Square. A tougher policy is suggested. This is a mistake. The Czechs would do better to ignore the drivel pouring out of Washington and Brussels about drugs and legalise them all.

Leaving aside the usual libertarian arguments - which, by the way, I fully accept - I say that drugs are not in themselves a serious problem. 50 years of well-funded research have failed to prove cannabis more dangerous in the long term than alcohol or tobacco. It may even be good for delaying glaucoma blindness and treating the symptoms of multiple sclerosis. It is not physically addictive. Nor, says Martindale's Pharmacopoeia, is cocaine. Nor is LSD.

Heroin, developed as a patent cough medicine, remains an unrivalled painkiller. Like the other opiates, it is addictive over time, but only a minority of users become addicted; and only a minority of addicts die.

Nor are drugs a menace in the actionable sense to third parties. Cannabis and the opiates are relaxants. Hardly any violent crime is committed under their influence. Cocaine, the psychedelic drugs and amphetamine can excite people to violence, but seldom do.

Nor would greater availability increase the amount of harm. The British past provides a compelling example. Until 1920, drug use was uncontrolled. Between 1827 and 1859, British opium consumption rose from 17,000lb to 61,000lb. Workmen mixed it in their beer. Gladstone took it in his coffee before speaking. Scott wrote The Bride of Lammermoor under its influence. Dickens and Wilkie Collins were both heavy users. Cannabis and heroin were openly on sale.

Yet most resulting deaths were individual accidents, and even these were negligible - excluding suicides, 104 in 1868 and thereafter to 1901 an annual average of 95. Temperance fanatics aside, and their first hate was alcohol, few saw any serious problem.

There are massive problems associated now with drugs. But these are almost wholly effects of prohibition.

When drugs are illegal, only criminals will supply them. And when criminals are allowed to dominate an entire market, they will be able - indeed required - to form extended, permanent structures of criminality that could never otherwise exist. They will then make drugs both expensive and dirty.

They will be expensive because bribes, transport inefficiencies, rewards of special risk, and so forth, all raise the costs of bringing drugs to market. Therefore much of the begging, prostitution and street crime that inconvenience Western cities. As many as two-thirds of American muggings may be to finance drug-use.

They will be dirty because illegal markets lack the usual safeguards of quality. When a can of beer is stamped "8% alcohol by volume", this does not mean anything between 0.5% and 30%. Nor will caustic soda be used to make it fizzy. Brewers have too much to lose by poisoning or defrauding customers. Drug dealers can afford to be less particular.

Therefore frequent overdosing. Therefore poisonous additives. Therefore, in 1986, an estimated 5% of Edinburgh heroin mainliners infected with AIDS caught from used needles.

Certainly, drug dealing in Wenceslas Square calls out for public action. It is an early sign of the urban degradation with which we in the West have long been familiar. But that action is not an augmenting of police powers. It is to let the pharmacies open their own trade in recreational drugs, and thereby to bankrupt the street dealers.

The Westernisers could do their countries still greater service if only they would stop slavishly copying the West, and instead recognise and learn from its mistakes. Then their advice would be that, in the War against Drugs, early surrender is by far the best policy.