The US is too bogged down in Afghanistan to engage Iran militarily over its nuclear program, an ex-CIA South Asia expert and current adviser to US President Barack Obama said in Tel Aviv on Tuesday. Bruce Riedel, a senior Brookings Institute and Saban Center fellow for political transitions in the Middle East and South Asia, addressed scholars and journalists at Tel Aviv University's Institute for National Security Studies. He warned that the US was fighting a losing battle against Taliban insurgents in Afghanistan, and that Washington would soon have to make difficult choices on beefing up troop levels there. "Israelis need to understand that there's going to be a huge drain on resources, attention and capital, and that will have implications," Riedel told The Jerusalem Post before his talk. He acknowledged that those implications would primarily affect the Iran question. During his address, Riedel referred to the US's commitments in Iraq and Afghanistan, and said, "We've got two wars. You've got to be bold to say, let's start a war against a third party, particularly when the third party can hit you in the first two fronts." The US has learned that it "can't fight two medium-sized wars simultaneously," he said. Riedel retired from the CIA in November 2006 after 30 years of service. In 2007, he was asked by then-senator Barack Obama to be an expert volunteer adviser on counterterrorism. "In June this year, the president called," Riedel said. Obama asked him to assemble a strategic review of US policy in Afghanistan and Pakistan. "The president has inherited a disastrous war that is being lost," Riedel said. "Pakistan, next-door to Afghanistan, is being destabilized. Pakistan is the fastest growing nuclear arms state in the world, and has more terrorists per square kilometer than any other country," he continued. Riedel said the scenario that kept him up at night was the potential for a jihadi sweep to power in Pakistan via a violent coup. "That is the nightmare outcome," he warned. Such a development would certainly destabilize the entire world, Riedel said, and would have severe implications for Israel, too. "Pakistan would be a patron state sponsor of terrorism. Hamas would find a lucrative Sunni sponsor," he added, noting that a jihadi Pakistan would be a more attractive patron to Hamas than its current sponsor, the Shi'ite Islamic Republic of Iran. "We're losing... It's getting worse in Afghanistan," Riedel said. The US could either remain in its current position, which would, in effect, mean that the Taliban would control the Afghan countryside and NATO forces would control the cities, or a decision can be made to withdraw, Riedel added. "President Obama has ruled that [a withdrawal] out. I think correctly," Riedel said. But the option of a troop surge was not simple either, he noted. "Every soldier sent to Afghanistan costs the US a million dollars a year. Thirty thousand soldiers cost $30 billion. Extremely large resources are involved," he said. "America is broke." Riedel's Afghanistan review ended with the conclusion that recent recommendations by US Gen. Stanley McCrystal, to send tens of thousands of more troops to Afghanistan, should be tried. "Within 18 to 24 months, we will know whether Obama inherited a dead patient on an operating table," Riedel said. "The question of sending more troops will define Obama's first term in office."