Of all the worst-case scenarios that could result if U.S. military involvement in Central Asia spirals out of control, one of the most nightmarish is the possibility that Pakistani Gen. Pervez Musharraf loses his grip on power, and the country’s nuclear weapons fall into the hands of Islamic extremists.

On Monday, the New Yorker’s Seymour Hersh reported that American special forces are prepared to sneak into Pakistan and disarm its nuclear weapons in the event that the conflict in Afghanistan destabilizes Musharraf’s government.

“The hunt for Osama bin Laden and his Al Qaeda network has evolved into a regional crisis that has put Pakistan’s nuclear arsenal at risk, exacerbated the instability of the government of General Pervez Musharraf, and raised the possibility of a nuclear conflict between Pakistan and India,” Hersh writes. “An ilite Pentagon undercover unit — trained to slip into foreign countries and find suspected nuclear weapons and disarm them if necessary — has explored plans for an operation inside Pakistan.” he writes.

But Musharraf and Pakistani officials have gone out of their way to try to reassure nervous Pakistanis and Western leaders that the nuclear arsenal is safe and Musharraf’s government is stable. Earlier this month, Musharraf reshuffled his top military brass, and replaced the head of the Pakistani intelligence service in a purge of officials who are seen as sympathetic to the Taliban. Pakistan’s president said there is no reason to fear for the stability of his government or its control of Pakistan’s nuclear weapons.

“Pakistan’s army is certainly the most disciplined army in the world and there is no chance of any extremism coming into the army,” he said. “I don’t see this doomsday scenario ever appearing.”

During his visit to Pakistan earlier this month, Secretary of State Colin Powell said he found Musharraf to be “very much in charge” of his government. “I found him to be in a secure position,” Powell said.

But Gary Milhollin, director of the Wisconsin Project on Nuclear Arms Control, headquartered in Washington, said there is still some cause for concern about the conflict in Afghanistan spreading to neighboring Pakistan. “The greatest risk is a fissure within Pakistan’s military caused by officers sympathetic to the Taliban,” he said.

As Musharraf tries to calm Western leaders, he must also placate religious fundamentalists within Pakistan’s borders. Among Pakistanis who harbor resentment toward the West, there is a saying that nothing happens in Pakistan without the blessing of the three A’s: Allah, the Army and America.

So it came as no surprise that Musharraf told Powell that the U.S. should try to end the bombing in Afghanistan as quickly as possible. “Certainly, a majority of the people are against the operation in Afghanistan,” Musharraf told reporters after his visit with the secretary of state. “They would like to see this operation terminated as fast as possible, and that is what I would urge the coalition.”

Clearly, Musharraf must still play both sides of the political aisle as the U.S. war in Afghanistan continues. As the general prepared to speak to the National Command Authority (NCA) last week — the agency that controls the nation’s nuclear weapons — religious leaders denounced him at a protest in Lahore. Qazi Hussain Ahmed, chief of the main religious party Jamat-i-Islami, declared Musharraf a “security risk,” saying that the military ruler has bargained away the country’s security and control of its nuclear program in exchange for aid dollars from the West.

Ahmed told another rally in Lahore over the weekend that religious groups were planning sit-in protests in Islamabad calling for Musharraf’s resignation. “We will go to Islamabad with full force and we will ask all religious parties to participate,” he said. “We will not call off the sit-in until the Musharraf government quits.”

Musharraf announced Sunday he would meet with Ahmed and other religious leaders soon to discuss the domestic crisis brewing as the U.S. attacks on Afghanistan continue.

But the protests have created concern about the stability and security of Pakistan’s nuclear arsenal. Last week, the Times of London reported that Pakistan had already handed over some nuclear materials to Osama bin Laden, which was flatly denied by Foreign Office spokesman Riaz Mohammed Khan. “These reports are absurd,” he said.

Maria Sultan, research fellow in the Institute of Strategic Studies (ISS), says Western fears about Pakistan’s nuclear security are unfounded, and that Pakistan’s nuclear weapons are protected by the very structure of the NCA.

“Pakistan’s command and control system is based on a central authoritative system; therefore there is lesser potential of accidental launches or misuse,” she explained. Control of the nuclear arsenal is divided among military, political and scientific bodies, a form of checks and balances created to prevent the weapons from falling into the wrong hands.

Also, Pakistan does not have its nuclear capability in so-called “push-button state.” That means “it would need a lot of synchronization with a larger number of personnel; hence some rogue element taking control is impossible,” Sultan pointed out. “Unlike the United States, there is no nuclear button in the hand of one person or one organization. If the threat of nuclear terrorism is to be considered as a viable option, any power which has the capability of producing nuclear fissile material even for civilian use is a source of threat,” she said.

Still, Michael Krepon, a nuclear weapons specialist at the Henry L. Stimson Center, said world leaders are understandably concerned about pro-Taliban forces toppling Musharraf’s government. “Such officers getting out of control would be the ultimate nightmare.”

And others inside Pakistan do not share Sultan’s sense of security. Zafar Jaspal, a strategic expert at the Islamabad Research Policy Institute, said that compared with other nuclear powers, Pakistan’s security systems leave much to be desired. “When one makes comparison with the other nuclear weapon states, particularly with reference to high-tech states, the [security system] is dubious,” Jaspal said. “To make it more effective, Pakistan needs technological assistance from the developed world.”

U.S. law, however, does not allow sharing such sensitive nuclear information with other countries. Clearly, the two countries’ alliance in the war against terrorism heralds greater cooperation on many different military and diplomatic fronts. But it is not yet clear how much and what kind of help the U.S. will offer Pakistan to keep its nukes under lock and key.

President Pervez Musharraf’s decision to replace the chief of Pakistan’s military intelligence agency and demote key military leaders could herald a significant step away from Afghanistan’s Taliban regime, experts say.

Coming on the eve of U.S. and British attacks on Afghanistan, the moves are being widely interpreted as a sign that Musharraf plans to use the global conflict to squelch Islamic militants in his country and strengthen his own secular government.

“This really shows the Islamic militants that the guys who have the guns do not like them,” says Stephen Cohen, senior fellow at the Brookings Institution. “Any question of an Islamic coup within the army is ruled out now, I think. There were some officers who favored more radical Islam, or at least wanted to use it to hold on to power. Now many of them are gone.”