This week President Yeltsin will be in Berlin to attend the event for which all decent Europeans have prayed for 50 years: the withdrawal of brutalising Russian troops from Gennany. Yet as they depart, our logical mood should be stark terror.

The shattered Russia to which dis-gruntled soldiers are returning seems liable to leak out enough private-enterprise-pinched plutonium to enable terrorists, mad mullahs and mafias to threaten to make some of the poshest centres of civilisation uninhabitable. Our Clintons, Kohls, Mitterrands and Majors desperately need to face the frightening facts. The danger is that these rather irresolute leaders may run away from these facts, so as to be polite to harassed Mr Yeltsin.

The central fact is that the ex-Soviet Disunion has some 130 tons of weapons-grade plutonium. This is relatively few lorries-full, but enough to make more than 16,000 nuclear bombs far more powerful than Hiroshima’s.

The Russians claim that not a gram is missing from their well-guarded stores, but they are fibbing. More than 300 grams have been found in four locations in West Germany, ranging from a suitcase carried by a Colmbian passenger off the Moscow flight to Munich, to a jamjar-full in a German businessman’s garage.

Documents seized with these small hauls suggest they were samples preliminary to larger shipments of several kilograms (ie, several thousands of grams), at an alleged Russian asking price of about £40m per kilogram. With only three kilograms, a state such as Iran might build a portable nuclear bomb, capable of completely destroying much more than the City of London’s square mile. There is comfort in the calculation that, in the lower-technology setting of an IRA safe-house bedsit in Kensington, bomb makers might need 12 times as much; that would work out at nearly £1½ billion a bomb, and even Clinton’s American-Irish classmates aren’t giving the IRA that. The Germans, though, think the inquiring customers for plutonium have included ETA, the Basque terrorists in Spain, as well as the governments of Iran, Saddam’s Iraq and (hotly denied) Pakistan

One of those arrested in Munich has said there may be 150 kilograms of weapons-grade nuclear material (ie, about 50 Hiroshima bombs’ worth) illegally circulating on the free markets of Europe. This is probably a story designed to make the 0.02% of that amount found in the suitcase associated with him look trivial. It is even more probable, however, that only a fraction of what is actually circulating has been found by Germany’s uniformed PC Plods, who are alone permitted to try to detect it. Kohl wants a new law to permit Germany’s secret service, armed with information from Russia (including from an anti-smuggling treaty in which Yeltsin co-operates), to join the hunt in Germany. Most German MPs oppose this, including his coalition partners. They say they want no new Gestapo. That is a classic case of politicians endangering the present by fighting the last war.

Germany’s Plods are now offering vast sums to anybody who reports smuggled nuclear material now inside their country. This has naturally led to increased exports of sub-weapons-standard plutonium and uranium from Russia, and from (please admit it) Russian military bases until this week inside Germany. Last Sunday's "terrorfocus" in this newspaper told of workers in Russia's civilian nuclear industry earning starvation pay that arrives late, who suddenly learn the plutonium with which they work every day is allegedly worth $50,000 per easily smugglable gram. One can argue about this sub-weapons-standard stuff, some of which turns dangerous. We should start to guard against it by hand-held Geiger counters on all frontiers. The guard by Geiger counter has precedents from the early 1960s, when the Americans thought either Russian or Chinese agents might carry in jig-saw-puzzle parts of a nuclear bomb. A dazzlingly attractive lady on my then viewspaper waltzed into New York's airport, dangling on her charm-bracelet a pebble from Dounreay's nuclear reactor, about
which some colleagues were even more nervous than I. The immigration officers behind screens, awaiting Mao’s hand-held bomb, saw their Geiger counters at last move. They converged armed on Mary in what turned into easily explained fun. It is no offence against civil liberties that we may often need to repeat that.

More immediately, we should concentrate on those fairly few tons of Russia’s weapons-grade pluto-nium. The West has proposed that American methods of nuclear control and accounting be applied to them. Yeltsin’s atomic energy min-ister has retorted that the West is trying “to foist on us the construction of new storage places and installation of their control systems. That would mean orders for their firms running into many millions”. This is absurd, as the West could certainly provide this assistance free.

Yeltsin’s real fear is his disgruntled army. When his last legions depart from Germany this week, journalists will discover the shame of airfields like Sperenberg, where the Russians have been subject to no German passport or customs controls whatever. Out of Sperenberg has flown much stolen property. Into it has come cargo for Russia’s mafias, probably including the prostitutes for the Frankfurt brothel where six people were murdered in a fight between rival Russian mafias this month. If American controllers appear in Russia’s secret military cities while this dirt spills, Yeltsin fears his army may turn even more nationalist and pro mad Vlad Zhirinovsky.

That nettle has to be seized. So does the nettle of customers for the private-enterprise nuclear material. I am not as scared as the French that fundamental Islam from North Af-rica might start a holy nuclear war against Europe. Since the Gulf conflict, even Libya’s Colonel Gadaffi has not been financing the explosion of airliners over Lockerbie, because he fears what would happen to him if he did. We have, however, had the wrong Western foreign policy since Clinton succeeded Bush.

On the one hand there are threats to invade nasty dictators such as Cuba’s and Haiti’s. That might make desperate and nasty dictators throw plutonium about. On the other hand there is a polite blind eye as Iran finances terrorism, and as the nuclear non-proliferation treaty loses all teeth. When Clinton agreed not to stop unstable North Korea from becoming a nuclear power, he said his avoidance of conflict in that region would let us sleep more peacefully in our beds. I toss more nervously in mine.