The turmoil in Egypt kept America's security and military leaders on edge Saturday, fearful of a worst-case scenario in which a massive arsenal supplied by the U.S. falls into the hands of Islamic extremists.

Egypt's massive military, with more than 1000 M1 Abrams battle tanks, 220 F-16 fighter jets and 150 attack helicopters including Apaches, has grown through the years after the historic peace settlement with Israel in the 1970s. U.S. foreign policy has seen investment in Egypt's military as a key to stability in the region. But with control of the country uncertain, that military becomes a wildcard.

"The substantial military resources of Egypt falling into the hands of an unknown future Egyptian government has a much greater potential to being a security risk for the US," said a U.S. military official, on condition of anonymity.

On Saturday, after the Egyptian cabinet formally resigned at the demand of Mubarak, an official who spoke to The Washington Examiner by phone said "no one is speaking [for the government] because in reality we have no government."

The Muslim Brotherhood, the largest opposition movement in Egypt, has called on President Hosni Mubarak, 82, to resign. The group is not listed by U.S. State Department as a terrorist organization, but many western analysts see its views as extremist. Egyptian law does not allow the Muslim Brotherhood to run for parliamentary elections, although some members run as independents.

James Carafano, senior defense analyst with the Heritage Foundation in Washington, said the situation in Egypt resembles the same shift in power during the Iranian Revolution in 1979, but that it is still too early to predict that Mubarak will be succeeded by an extremist government.

Carafano compared the Obama administration's Middle East policies with those of former President Jimmy Carter's before the revolution in Iran.

"If Egypt became an Islamist state it would be a huge setback for the administration," Carafano said. "In the last two years, Obama played nice with Iran, made speeches in Cairo and pushed for talks with the Palestinians" instead of holding those accountable for their actions and policies.

Saudi Arabia, Jordan, Algeria and Yemen, among a number of other Muslim nations, could potentially see similar uprisings in their nations, said Chistopher Boucek, a Yemen specialist with the Carnegie Endowment for International Peace.

"I wouldn't think that a month ago anybody would of thought that the Tunisian government would fall or that this would happen in Egypt," Boucek said. "Even Middle East experts didn't see this coming. So we certainly have to be mindful that it could happen almost anywhere else in the Middle East where governance is weak and the people are frustrated."

Sara A. Carter is The Washington Examiner's national security correspondent. She can be reached at