It was all smiles and little agreement during the Afghan president's visit to America, writes Graham Usher in New York Six weeks is a long time between "allies". In March United States President Barack Obama publicly upbraided Hamid Karzai for not acting against graft in his government. The lecture followed a leaked but widely publicised memo from the United States ambassador in Kabul that the Afghan president was "not an adequate strategic partner" to turn round America's losing war in Afghanistan. In a furious response Karzai accused Western governments, the United Nations and European Union of trying to rig last year's presidential elections against him. (In fact, he rigged the poll in favour of himself, courtesy of one million purloined votes). He also warned his erstwhile Western backers that "in countries like Afghanistan ... a very thin curtain distinguishes between cooperation and assistance with the invasion" by US and NATO forces. According to one source, so convinced was Karzai that the US and Britain were out to get him he threatened to "join the Taliban". During Karzai's four-day state visit to Washington last week the past was airbrushed. "With respect to perceived tensions between the US and Afghan government... a lot of them were simply overstated," said President Obama on 12 May at White House press conference, replete with smiles and rigorous stage management. Karzai blushed like a maid. The words "graft" and "inadequate" were cut: only "strategic partnership" remained. But the tensions were not overstated. They have been suppressed in the name a foreign war that for the Obama administration is now simply too big to fail. In the last year the president has increased US strength in Afghanistan to 100,000 troops, soon to outstrip Iraq as America's largest occupation. They are on the brink of taking the war to Kandahar, birthplace of the Taliban and hub of an insurgency that according to a recent Pentagon survey commands more support across more districts than the Karzai government. The aim is to reverse the tide so that American troops can start withdrawing from a deeply unpopular front by July 2011. Nothing Karzai has done in the last six weeks has altered American perceptions that he is incapable of delivering the governance required to win back popular support for a discredited regime, says Richard Fontaine, a former US foreign policy advisor. But "it's sunk in, after the Afghan elections last year, that this is the guy who's going to be here for four years and change, so we better get along with him because we don't have an alternative," he told the New York Times on 11 May. But it's not clear whether Karzai will change, or even if it would be wise to do so. Take the imminent Kandahar campaign. Obama, backed by his generals, believes reclaiming Kandahar is critical to "reverse the momentum of the insurgency" so that power can be transferred to a reformed Afghan government and Afghan soldiers can replace American ones. Karzai is sceptical, and not just because his brother, Ahmed Wali Karzai, runs Kandahar like a fiefdom for his tribe and is the single biggest cause of the government's lack of legitimacy in the province. There is also public opinion. A recent survey in Kandahar -- a city of half a million people -- found that 94 per cent of respondents opposed any operation by foreign forces. They have seen the trial run in Marja, where, since February, the largest ever American military campaign since 2001 has yet to clear fewer than 200 Taliban fighters. Marja is one fourth the size of Kandahar. And there are thousands of Taliban in that city and its hinterlands, many infiltrating from sanctuaries in Pakistan. In Marja the only thing the "surge" has brought locals is a spike in civilian deaths, usually from US checkpoints and convoys, the very armour supposed to protect them. It's bound to be bloodier in Kandahar. Most Afghans know this is a war that can't be won, and only ended through negotiations with the Taliban. Karzai agrees. On 29 May he has called a peace jirga or council of 1500 Afghan elders and leaders to "chart a way forward for engaging those who fight against us". Ostensibly Obama supports this. America too wants to "open the door to Taliban who have cut their ties to al Qaeda and renounce violence," he said. But the apparent agreement masks differences. While not averse to talking to the Taliban eventually, Obama believes the Kandahar offensive must first "soften" them up, to prise away foot-soldiers from leaders and make the leadership pliable to America's terms. "We want to be in a better position to make a deal," says a US government official. Karzai believes any meaningful deal will have to include the Taliban leadership, including Mullah Omar, and their backers in the Pakistani army and intelligence. He also suspects -- like them -- that for all America's talk of a long-term commitment to Afghanistan the surge is more likely a last show of strength so that US soldiers can go home passing off defeat as victory. At which point Karzai and his allies will be left without the invaders but with an insurgency the overwhelming majority of which is Afghan. He is "wondering who his protectors will be after 2011," muses one European diplomat. "Will it be the Taliban?"