If you think Iran is scary, just consider what would happen if Islamic extremists took over Pakistan. It's a very real possibility in that increasing worrisome country that helped spawn to the Taliban, and which Foreign Policy magazine has called "the country most likely to transfer nuclear technology to terrorists." That is the conclusion of 69 of 100 national security experts surveyed for the publication's "Terrorism Index 2008." More than half responded that Pakistan is "most likely to serve as al-Qaida's next home base." "We're all really worried that a radical theocracy like Iran will get the bomb, but what if the bomb gets a radical theocracy?" asked a Washington defense analyst speaking on background. Iran may be getting all the attention from Israel and the United States, but shaky Pakistan is the only Islamic nuclear power. Iran may boast of great strides in its pursuit of nuclear, missile and satellite technology, but analysts say its progress is no match for its overblown rhetoric. BUT PAKISTAN doesn't need to boast. It already has a stockpile estimated at 60 or more nuclear warheads and North Korean ballistic missiles and US-made F-16s to deliver them; target one is India, but in the hands of an extremist Islamist regime that could easily shift to Israel. Washington has reportedly spent more than $100 million to help secure Pakistan's nuclear arsenal, although it does not even know its size or location. Pakistan is a failed nation state. It has an unstable government on the verge of collapse, a tenuous flirtation with democracy, a coup-inclined military with ties to the Taliban, and an upcoming presidential election in which the front-runner's lawyers contend he suffers from dementia and depression. It also has sold nuclear technology to Iran, Libya and North Korea. Growing Islamization of state institutions and policies, notably the schools, is legitimizing religious extremism. Many Taliban trace their roots to Pakistani madrassas. MOST IMPORTANT, Pakistan's porous border with Afghanistan is a sanctuary and training ground for the Taliban resurgence and al-Qaida. Osama bin Laden is believed to be holed up in those areas which are more hospitable to the Islamic extremists than the Pakistani government and army, which has been unable or unwilling to do much about it. In fact, Western experts believe elements of Pakistan's military and its powerful intelligence service, ISI, are working with the Taliban. The new army leader, Gen. Ashfaq Kiyani, recently stepped down as head of the agency. Pakistan, said the defense analyst, is "the scariest place on Earth." It could splinter if powerful ethnic groups like the Pashtun and the Baluch seek to break away and form their own states. Or there could be yet another military coup, this time led by the ISI elements close to the Taliban. Hamid Karzai, the pro-US president of Afghanistan, has accused Pakistan of giving the Taliban sanctuary and bases to attack his country, and ISI has been accused of being behind attempts on his life. A recent Council on Foreign Relations report said ISI is believed to have links to terrorist groups in several countries, including England, India, Afghanistan and Iraq. ISI-Taliban cooperation goes back nearly 30 years, and many of its agents "have ethnic and cultural ties to Afghan insurgents and naturally sympathize with them," according to Frederic Grare of the Carnegie Endowment for International Peace. Author Steve Coll, an expert on the Taliban, has called it "an asset of the ISI" and "a proxy force, a client of the Pakistan army." The Pentagon sees the deteriorating situation in Pakistan as increasingly dangerous. The chairman of the Joint Chiefs of Staff, Adm. Mike Mullen, flew out to the Indian Ocean last week to convene a highly unusual secret meeting of senior American and Pakistani commanders aboard the aircraft carrier USS Abraham Lincoln. His message: You've got to do more to combat the militants who have found sanctuary in the border areas of Afghanistan and Pakistan and are responsible for the rising number of US and NATO casualties. He wants Pakistan to allow US Special Operations forces to operate more freely in those areas. THERE ARE serious questions as to which side the Pakistani military and ISI are really on. US President George W. Bush has reportedly complained that some ISI elements are leaking US intelligence information to the Taliban and aiding militants' attacks on US and NATO forces in Afghanistan. A coup led by pro-Taliban elements would put that country's nuclear arsenal in the hands of some of the world's most dangerous Islamic extremists. Pakistani journalist Ahmed Rashid writes that "Islamic extremism is gaining strength" in his country, and warns that the army may insist that a pro-Taliban Islamic party, the Jamiat Ulema-i-Islam, be part of any future government. Pakistan may be the greatest challenge awaiting the next president of the United States, but so far it has been getting scant attention in either campaign.