Pakistan's hopes for civil nuclear cooperation have been a non-starter in Washington, but experts say the United States can use it as a dangling carrot as it seeks influence in Islamabad.
The two nations Thursday wrapped up a first-of-a-kind "strategic dialogue," which the United States hopes will show Pakistan's widely anti-American public that it cares about the country beyond seeking help against Islamic extremists.
US officials stayed carefully on message, pledging respect for Pakistan and never explicitly saying no to its requests -- a refusal that would have been sure to steal the headlines.
Pakistan is seeking a civilian nuclear deal along the lines of a landmark agreement that the United States struck with India in 2008. The South Asian rivals stunned the world in 1998 by carrying out nuclear tests.
Asked about the Pakistani request, Secretary of State Hillary Clinton said the United States would listen to "whatever issues the delegation raises" and highlighted a 125-million-dollar US package to boost Pakistan's energy sector.
A nuclear deal could help ease the developing country's chronic energy shortages. But it would also amount to US recognition of Pakistan as the Islamic world's only nuclear power, a point of pride for many Pakistanis.
"At the moment this looks like a non-starter, but it shouldn't be," said Marvin Weinbaum, a scholar at the Middle East Institute and former State Department official.
"There is no reason why we couldn't use this as a bargaining tool to get more cooperation, to say, 'This may not be something we can deliver now, but we would like to work something out with you,'" he said.
"It could have a very positive impact both with the Pakistani elite and public."
But the United States has longstanding concerns about proliferation from Pakistan -- and policymakers are said to have quietly drafted a crisis plan in case the nuclear arsenal risk falling out of government control.
The father of Pakistan's bomb, Abdul Qadeer Khan, has admitted leaking nuclear secrets to Iran, Libya and North Korea, although he later retracted his remarks.
The level of separation between Pakistan's military and civilian nuclear programs also remains a matter of dispute. Pakistan returned to civilian rule in 2008 and President Asif Ali Zardari a year later handed over control of the nuclear program to Prime Minister Yousuf Raza Gilani.
"I think it's extremely premature to be talking about any civil nuclear cooperation between the US and Pakistan at this stage," said Lisa Curtis, a senior fellow at the Heritage Foundation think-tank.
"It would be more appropriate and important to be talking about conventional military cooperation, economic support and breaking down trade barriers," said Curtis, who served in the State Department in former president George W. Bush's administration.
Bush championed the nuclear deal with India, the signature part of his drive to build an alliance between the world's two largest democracies.
The agreement faced criticism from some members of President Barack Obama's Democratic Party, who argued that it sent the wrong message as India, like Pakistan and Israel, refuses to sign the nuclear Non-Proliferation Treaty.
"One of the reasons the US was able to move forward in Congress was because of India's solid record against proliferation and Pakistan doesn't have that," Curtis said.
Some critics who believe the Bush agreement was too easy on India said that Pakistan's requests confirmed their fears.
"I think the fact that we gave India such a sweetheart deal set a very dangerous precedent and it's no surprise that Pakistan wants a similar deal," said Leonor Tomero of the Center for Arms Control and Non-Proliferation.
She also said that Pakistan's request was "odd" coming so close to Obama's April 12-13 nuclear security summit in Washington and the Non-Proliferation Treaty review conference a month later.