It is an open secret in Tajikistan, the former Soviet republic of 5 million people, that fear of Afghanistan is the key to why Russia and Uzbekistan helped old-guard Tajik Communists and southern clansmen to crush a 10-week takeover by an Islamic-democratic opposition alliance. The Russian armoured personnel carriers and anti-mine vehicles were due to help attack remnants of the Tajik opposition near the Afghan border which are being forced slowly back into the mountain fastnesses of the Garm valley and Badakhshan, Russian officers said.
Participation of Russians in the Tajik civil war has become so regular that municipal water trucks arrived 10 minutes after the convoy's departure to wash the mud from its tank tracks off the city boulevard. But as Russia's new policy to stabilise unrest in the Soviet dependencies of Central Asia acknowledges, the main target - to prevent trouble spreading from Afghanistan - also entails the risk of Moscow's entanglement.
All minds are focused on a probable guerrilla offensive in the spring and possible terrorist attacks in Dushanbe by the opposition, only part of an equation becoming entangled with Afghan unknowns.
Afghan involvement comes in many forms. One is ideological, with Gulbuddin Hekmatyar's Islamic mujahedin supporting the defeated Tajik Muslims. Another danger is aggravation of an ethnic divide between Tajikistan's majority Tajiks and minority Uzbeks if there is a breakdown in a rumoured agreement in northern Afghanistan between Ahmed Shah Massoud and Afghan Tajiks, and General Abdul Rashid Dostam and Afghan Uzbeks. A third factor is money. Eastern Tajikistan now harbours an important new drug- and weapons-trading route that supplies Afghan heroin through the former Soviet Union to lucrative markets in the West.
'All this talk of Communists winning and Islamics losing is an exaggeration, a smokescreen. It is just cover for what is basically an Afghan drug- and gun-war,' said one of the few ambassadors left in Tajikistan. The Dushanbe government handed a diplomatic note to Afghanistan this week to protest against 24 armed incursions in the past month, which often involved the capture of drugs and guns.
Another aspect is pure power politics, with Mr Massoud needing to cover his back in Tajikistan in case the power-hungry Mr Hekmatyar, his war chest filled by Saudi Arabian Wahhabi fundamentalists, manages to take control of the Tajik opposition.
Mr Hekmatyar has started to arm and train the thousands of Tajik refugees in areas under his control, forcing foreign aid agencies to abandon work there. About 53,000 Tajik refugees have fled the war in northern Afghanistan in the past two months, and perhaps half are believed to be virtual hostages of such Afghan warlords.
Afghan and Islamic infiltration of Tajikistan is the main reason Russians give for backing Imamali Rakhmanov, who was elected acting president in November. His government is on the same wavelength as Moscow, Washington and fellow conservative Central Asian states over the need to stop the spread of Afghan-style violence and drug mafias.
'It's not the same as the Baltics here. They want to be free of the Russian army. But the Baltic states don't have a neighbour who has as many guns as the Afghans, they are not intimidated the way we are,' said Rashid Alimov, the Tajik Foreign Minister. But Russian officers admit it was a tough job to control the 750-mile border with Afghanistan and China even in Soviet times. Now, despite promises of reinforcements, Russian border guards and army units are seriously undermanned. The 201st Motorised Infantry Division in the Dushanbe garrison has plenty of hardware but only 25 per cent of its nominal strength of 10,000 men.
'There is no co-ordination, no strategy. It would be nice to have a phone call from Moscow sometimes, but they have their own problems,' said one officer.
Two transport helicopters are all that have arrived from a promised 2,000-man contingent pledged by Russia and Central Asian states to help the Dushanbe government. Uzbekistan, increasingly the arbiter of Tajik affairs, quietly does a great deal more.
Russian officers maintain that they run little risk of getting bogged down in a second Afghan war in Tajikistan because they believe Tajiks are less aggressive than Afghans and are accustomed to Russian ways after 70 years of Soviet rule.
But even two months after the change of government in Dushanbe, an all-night curfew has not stopped the sporadic sound of unexplained gunfire at night. Whatever happens with Afghanistan, diplomats are sure there will be no clean finish to the Tajik war.