Russian news agency Interfax is reporting that Russia is pressing Tajikistan to allow its troops to resume border defense duties in an effort to stem the flow of drugs coming from Afghanistan.The border between Tajikistan and Afghanistan is long and hard to guard. In some sections, all that separates the two countries in narrow high-walled gullies is a shallow, unfenced and fast-moving river. It is often possible to drive for hours on the barely paved road running alongside the border before coming across any signs of a military presence.Not surprising, therefore, that Moscow should be applying relentless pressure to be enabled to supplement Tajikistan's tightly stretched frontier forces. But, as one unnamed Tajik source tells Interfax: "Very complex negotiations are under way; Russia wants to return to this geopolitically important southern border of the CIS [Commonwealth of Independent States], but Tajikistan is still cool to the idea."Reuters cites anonymous security sources and analysts saying Russia may seek to send up to 3,000 border guards to Tajikistan. Russian border troops left Tajikistan in 2005 in a development that seemed to mark yet another stage of Moscow's gradual strategic withdrawal from the region. But with the drug problem in Russia showing no sign of abating, the emphasis has now moved from broad issues of strategy to more pragmatic areas. Russia officials have expressed concern that the eventual pullout of US troops from Afghanistan will only serve to deepen instability, which will in turn further exacerbate the drug trade.Interfax's source suggests Tajikistan's intractability may be down to a matter of pride: "It is not politically profitable for Tajikistan to once again transfer border protection responsibilities to Moscow. It will look like we have failed to do the job and have asked our 'big brother' for help."As the Interfax report also notes, border service officials from the two countries met in Dushanbe in February to discuss security cooperation, but the details of those talks are not known. Tajikistan's officials staunchly deny there has been any talk of a return of Russian border guards, but that is clearly not the full truth. One also has to wonder whether there is more to Tajikistan's reluctance to welcome back the Russians than mere pride.The scale of the drug trafficking industry in Tajikistan has inevitably given rise to a rich, powerful and influential criminal business class that even the authorities must contend with. Islamist militants have faced the full force of Tajikistan security forces, but no such measures would appear to apply to the drug barons that arguably pose an even greater risk to Tajik society.If there is some kind of accommodation between the government and drug traders, the last thing President Emomali Rakhmon wants is Russians meddling with the set-up.