ISLAMABAD/WASHINGTON U.S. ties with Pakistan following Osama bin Laden's death are teetering on the brink, threatening to choke off Washington's ability to supply the Afghan war and to deprive Pakistan of desperately needed aid.
But neither country is likely to sever a relationship that, while maddening for both sides, has helped give Pakistan global clout and allowed the United States to strike at militants it sees fueling violence in Afghanistan.
"There's still a great deal of policy churn going on in Washington. I think the mood is a little dark right now," a U.S. official said on condition of anonymity.
"I think the ultimate decision is that it will be in our national interest to maintain some kind of workable relationship," the official said. "Because, after all, Pakistan is a country in a very tough neighborhood."
Two weeks after U.S. Navy SEALs descended on a house near Islamabad and killed bin Laden, the Obama administration is seeking a new course for bilateral ties with a dubious ally against militants.
In Pakistan, military and civilian leaders are facing unprecedented criticism because bin Laden, whose al Qaeda organization was behind the September 11 attacks on the United States, apparently was living undetected for years in the city of Abbottabad and because many Pakistanis see the unilateral raid as a violation of their sovereignty.
The White House insists it will continue cooperation with Pakistan but officials acknowledge privately that talks with counterparts in Islamabad have been very tense as both sides brace for possible revelations from the computer data and other material seized from bin Laden's compound.
On Saturday, Pakistan's parliament condemned the U.S. raid, warning Pakistan might cut the main supply line for U.S. forces in Afghanistan through the Torkham border crossing in western Pakistan.
The chairman of Pakistan's joint chiefs of staff committee also canceled a five-day U.S. visit expected this month.
Some U.S. lawmakers want to curtail or cut off generous U.S. military and development aid to Pakistan, which has amounted to some $20 billion since 2001.
"Our problems with Pakistan are a symptom of 30 years of failed policy," said Vali Nasr, who until last month was a senior State Department advisor on Pakistan. "We abandoned them after the Afghan war; we turned toward India; we punished them with the Pressler Amendment," which clamped down on aid and commerce in the 1990s.
"You cannot fix that with one year of engagement. Fixing this issue is a long-term issue," Nasr said.
Retired Pakistani general Talat Masood said the awareness in Washington that Pakistani support is pivotal to peace talks in Afghanistan -- where President Barack Obama will initiate a withdrawal this summer despite record violence -- is another factor that may help salvage bilateral ties.
"The fact remains they cannot afford to cut off the aid and will keep the relationship going," Masood said.
TOEING THE LINE?
The startling events surround bin Laden's death come just months after the arrest of Raymond Davis, the CIA contractor who spent six weeks in a Lahore jail for shooting two Pakistanis, seriously strained bilateral relations.
Yet there are signs that Pakistan will be willing to toe the line. On Friday, a U.S. official said Pakistan had allowed authorities to interview three of bin Laden's widows.
Neither has Pakistan moved to halt U.S. drone strikes on militants in western Pakistan, the United States' main tool for acting against insurgents who helped make 2010 the bloodiest year yet for the Afghan war, even though they have fueled popular anger against Pakistani leaders.
U.S. officials say there are "absolutely no plans" to drop a missile program it sees as crucial to success in Afghanistan.
If there is nothing found in the data seized from bin Laden's compound that implicates Pakistani leadership, it seems likely the mutual rancor will subside.
Senior Democratic Senator John Kerry, an unofficial envoy to Pakistan who will arrive there in the coming days, has advocated keeping the relationship intact. Leaders of both parties in the U.S. Congress have not yet embraced calls from other lawmakers to halt aid.
"The U.S. must avoid abrupt action like stopping all aid, which would come at a steep price to U.S. interests in the region," Lisa Curtis, a former CIA analyst and State Department official, wrote this week.
Analysts say that an end to aid from the United States, or the multilateral lenders it supports, would devastate Pakistan's economy and push it closer to Western rival China.
"The chance of Pakistan's nuclear arsenal falling into terrorist hands, while currently remote, would increase in the context of a deteriorating political and economic situation," Curtis wrote.
(Additional reporting by Susan Cornwell in Washington; Editing by Bill Trott)