How long can US troops withstand rupture of Pakistan supply lines?

Pentagon officials are wrestling with how much longer they can withstand the rupture of vital supply lines into Afghanistan, amid news of another dramatic attack in Pakistan Wednesday that left more than two dozen fuel tankers bound for US bases in flames and one driver reportedly dead.

Complicating matters for the US military, the attacks come on the heels of the closure of a key border-crossing point at Torkham Gate after a US helicopter in hot pursuit of insurgents accidentally killed three Pakistani troops – and left Pentagon officials scrambling to smooth relations with their Pakistani counterparts.

Half of the supplies for US and NATO troops come through Pakistan via multiple routes, according to US military officials.

The fuel supply is of particular source of concern, Pentagon spokesman Geoff Morrell said in a briefing with reporters Tuesday. “What’s consequential about Pakistan, in terms of … the Torkham Gate, is how much fuel does come through there for our forces.”

Curtailing fuel consumption had already become part of US military strategy, according to officials who say they now consider it a matter of national security. The more US convoys that carry fuel to bases around Afghanistan, they add, the more US troops who are at risk.

The Defense Department has also been pursuing the expansion of an agreement with Russia that would allow the transport of more supplies through Russian territory. The agreement permits building material, food, and water, but precludes ammunition and weapons from moving overland. The US military got some relief last year, in advance of the surge of US forces into Afghanistan, when the US and Russia signed a “lethal transit agreement” that allows 4,500 flights per year filled with US arms and other supplies through Russia, according to US military officials.

Today some 30 percent of US troop supplies travel through a northern distribution network that includes Russia and several former Soviet republics, but the importance of Pakistan to the supply line means that the Pentagon is “obviously watching it closely” and continues to investigate additional supply routes, says Col. Dave Lapan, a Pentagon spokesman. “The longer that it went on, we would look at other alternatives. It’s something they assess day by day and determine whether they need to use other means to supply.”

The military has yet to see the effect of the closure on operations, he adds, noting there are stores of supplies in Afghanistan for US troops. Other supply lines remain open, moreover, though the attacks of recent days on supply convoys show they are vulnerable.

Pentagon officials also say there have been upticks in violence against fuel convoys before, and they sought to put the best face possible on why the Pakistanis' closed Torkham Gate after the deaths of the three Pakistani troops. “The stated public reasons for the closure of Torkham Gate was to protect the convoys – that in the aftermath of the cross-border assault and the killing of these three frontier corpsmen, that [Pakistan] thought it was best to shut down the gate, I suppose to eliminate the possibility of there being attacks as the convoys moved through that narrow passageway between Pakistan and Afghanistan,” Mr. Morrell offered.

While defense officials say military relations between the US and Pakistan are solid, they concede that the Pakistani government remains concerned about the Pakistani public's perceptions of US incursions into the country and its own sovereignty.

US officials say they hope to resolve the latest manifestation of that tension, the Torkham Gate closure, by week’s end.

“We haven’t seen anything to indicate otherwise,” says Lapan, citing statements from Pakistani officials who indicated that the gate would be closed for one week.

For now, the hope at the Pentagon is that results of the investigation into the NATO operation that killed the three Pakistani troops, expected later this week, will speed the opening of the key crossing. “It should sort of explain what happened – and it was a joint investigation with the Pakistanis,” Lapan says, “so getting that out there should hopefully help.”