The American spy’s hurried departure is the latest evidence of mounting tensions between two uneasy allies, with the Obama administration’s strategy for ending the war in Afghanistan hinging on the cooperation of Pakistan in the hunt for militants in the mountains that border those two countries. The tensions could intensify in the coming months with the prospect of more American pressure on Pakistan…

The American officials said they strongly suspected that operatives of Pakistan’s powerful spy service, the Directorate for Inter-Services Intelligence, had a hand in revealing the C.I.A. officer’s identity — possibly in retaliation for a civil lawsuit filed in Brooklyn last month implicating the ISI chief in the Mumbai terrorist attacks of November 2008…

The mistrust between the C.I.A. and ISI, two uneasy but co-dependent allies, could hardly come at a worse time. The Obama administration’s Afghan war strategy depends on greater cooperation from Pakistan to hunt militants in the country’s western mountains, and yet if Pakistan considers Washington’s demands excessive, it could order an end to the C.I.A. drone campaign.