The U.S. and Pakistan have a history of troubled relations that started well before the terrorist attacks of Sept. 11, 2001. The road has grown only rockier since then. Despite giving Pakistan billions of dollars in aid over the past decade, anti-Americanism is widespread in Pakistan. And after years of sometimes meaningful cooperation in hunting down al-Qaida figures, Pakistan is still seen by many U.S. officials as double-dealing and unreliable.
The transit route issue was a distraction and an embarrassment for the United States at the summit, and Obama's cool arm's length treatment of Zardari made it look even worse for the Pakistani president.
"Pakistan has to be part of the solution in Afghanistan, and it is in our national interests that to see a Pakistan that is democratic, that is prosperous and that is stable," Obama said.
The quarrel over supply routes is intertwined with several other disputes, including Pakistan's opposition to U.S. drone strikes against terrorist targets inside its borders.
In addition to closing the border crossings in response to the November attack, Pakistan ordered the U.S. to vacate Shamsi air base, which the U.S. was using to launch drone strikes at al-Qaida and Taliban militants.
The top allied commander in Afghanistan, Marine Gen. John Allen, has tried to cast the supply route problem in the best possible light, while acknowledging that he'd like to see the border crossings reopened as soon as possible. Allen said Sunday that by some measure, war stocks are higher now than when the crossings were closed.
That is thanks to an increased — and much more costly — use of alternative routes, including a network of northern routes that connect Baltic and Caspian Sea ports with Afghanistan through Russia and Central Asia and the Caucasus. And they combine sea, rail and truck transport and are more costly than crossing Pakistan by land.
U.S. officials have offered a range of estimates on how much the closing of the Pakistani land routes have added to the overall supply costs, but it apparently is at least two or three times more expensive to move supplies by air and via the northern route.
To underline the value of those alternative supply routes from the north, Defense Secretary Leon Panetta met Monday in Chicago with his counterparts from the central Asian nations of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. He expressed his "deep appreciation for their support" of the northern supply route, Pentagon press secretary George Little said.
At least as troublesome as being forced to use alternative supply routes into Afghanistan is the issue of how to get war materiel out of the country as Allen begins the withdrawal of thousands of U.S. troops this summer. That's because the withdrawal includes shipment of vehicles and other equipment that would be costly and time consuming to remove by air.
The NATO alliance needs Pakistan's cooperation to ensure Afghanistan's long-term stability and security, NATO's top officer told reporters. That was a mild way of saying that Pakistan can play the spoiler at will and holds cards the fighting force does not. Pakistan shares history, culture and language with Afghanistan's restive southern swath, and maintains support for Taliban-led insurgents who cross the border to kill U.S. and NATO forces.
Burns reported from Washington.
Associated Press writer Desmond Butler contributed to this report.
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