The most senior allied general in Afghanistan has said the war against the Taliban is likely to fail unless he is given more troops and a new strategy.The grim warning comes from top US and NATO commander Stanley McChrystal in a confidential assessment obtained by The Washington Post. He says that despite some progress, many indicators point to a general deterioration in the overall state of the country. And he urges a radical shift in how the campaign is being waged, with as much emphasis on gaining the support of Afghans as on killing insurgents. The number of US troops in Afghanistan has almost doubled this year to 62,000. A formal request for more, set to be made by General McChrystal in the coming weeks, would pile pressure on President Obama. Opinion polls show the American people are turning against the nearly eight-year-old war.