In a repeat of the 19th Century "Great Game", when the Russians and British competed for relations with Muslim leaders on the outposts of their empires, Mr Obama's envoys are scuttling between the palaces of Central Asia's post-Soviet dictators. In the last three months, Mr Obama has cut deals with Presidents Islam Karimov of Uzbekistan and Kurmanbek Bakiyev of Kyrgyzstan. Mr Karimov has been accused by a former British ambassador of ordering two opponents boiled alive. One of Mr Bakiyev's critics was recently stabbed 26 times in the buttocks by unknown assailants.

US diplomats have also paid calls on Ashgabad, the capital of Turkmenistan, a country still reeling from the personality cult of "Turkmenbashi", as the late President Sapurmurat Niyazov styled himself during his eccentric 19-year rule. "The United States is fixated by Afghan issues and does not care if it supports dictators," Tashbulat Yuldashev, a former Uzbek government official turned dissident told The Telegraph.

He fled Uzbekistan last year under threat from gangs of heavies after criticising Mr Karimov, president since the fall of the Soviet Union eighteen years ago. Mr Obama has brought a new pragmatism to foreign policy, disappointing those who expected his liberal idealism to dominate all aspects of his administration. That pragmatism is now being employed on one of the great diplomatic battlegrounds of history: the Silk Road through Central Asia, for decades closed off as part of the Soviet Union but now once again open to the exchange of goods, people – and unrest.

In the Fergana Valley, which straddles Kyrgyzstan and Uzbekistan and is close to Afghanistan, Islamic militants have found ready recruiting grounds in the hundreds of thousands of migrant workers who have lost their jobs in the financial crisis. Nine jihadists were killed in gun-battles near the city of Osh, on the Kyrgyz side of the border in June alone, while Uzbek identity cards have been found on dead Taliban fighters in Pakistan. Such incidents have made security more of a priority for both countries and America. Four years ago Mr Bush decided he could no longer tolerate Mr Karimov's politics after troops opened fire on an uprising in the eastern city of Andijan with the loss of hundreds of lives.

In retaliation for American criticism, Mr Karimov closed down a US air base that had been established as Mr Bush took his "war on terror" to neighbouring Afghanistan. The British ambassador to Tashkent, Craig Murray, had also written a detailed attack on the US-Uzbek alliance, claiming that Mr Karimov had tortured and killed opponents. But after Mr Obama's first approaches this year, Mr Karimov authorised the use of a US base as part of supplying the new US surge of troops into Afghanistan. Mr Karimov's record has hardly changed however. Human Rights Watch says 6,000 people are currently incarcerated in Uzbekistan for "non-violent religious offences". Journalists and activists continue to be imprisoned.

Freedoms are deteriorating in Kyrgyzstan too. Four years ago it was the great hope of US policy after the "tulip revolution" which, strongly influenced by American-backed civil rights groups, threw out Askar Akayev, the Soviet-era leader, and replaced him with Mr Bakiyev, an opposition figurehead. Mr Bakiyev, however, turned on the Americans, expelling two US diplomats and repeatedly threatening to close down the United States's second Central Asian military base near Bishkek.

He also renewed the country's close ties to Russia. A journalist who in February attacked that policy as seeking "oxygen for a sinking submarine" was subsequently set upon by men with metal bars who broke his ribs, arms and a leg and stabbed him repeatedly in the buttocks. Another critic, Medet Sadyrkulov, a former head of Mr Bakiyev's administration, was found dead in his burned-out car in March. Despite this, Mr Obama has agreed to triple the fee the US government pays for the use of the air base to keep it open to $60 million, with another $120 million in aid.

A senior Obama administration official disagreed with the suggestion that democracy activists were being ignored. “We engage both government and non-governmental leaders in the region. We do not one at the expense of the other,” he said, adding that William Burns, under secretary of state for political affairs, recently toured Central Asia and raised concerned about human rights and democracy with "every head of state he met". "There is the notion that engaging allows you to address these issues better than not engaging,” said the official, adding that the US maintained support for pro-democracy projects in the region.

The region's diplomatic sands shift fast and no-one can predict how long the new alliances will last. But Mr Yuldashev, the dissident, said rulers like Mr Karimov were adept at playing "divide and rule" to make their own leadership seem indispensable. "Democracy in Uzbekistan has no financial support any more from the United States," he said. "It only cares about Afghanistan." The Telegraph