Most nations, including many close allies of the United States, require as much as a weeks notice before U.S. warplanes are allowed to cross their territory. Not Egypt, which offers near-automatic approval for military overflights to resupply the war effort in Afghanistan or to carry out counterterrorism operations in the Middle East, Southwest Asia or the Horn of Africa.
Losing that route could significantly increase flight times to the region.
U.S. warships are also allowed to cut to the front of the line through the Suez Canal in times of crisis, even when oil tankers are stacked up like cars on an interstate highway at rush hour. Without Egypts cooperation, military missions could take days longer.
Those are some of the largely invisible ways the Egyptian military has assisted the United States as it pursues its national security interests across the region and why the generals now in charge in Cairo are not without their own leverage in dealing with Washington even after President Barack Obamas condemnation Thursday of the militarys bloody crackdown on supporters of the former president, Mohammed Morsi.
In his first overtly punitive step, Obama canceled the Bright Star military exercise, the largest and most visible sign of cooperation between the armed forces of the two nations. But given the growing violence in Egypt, it might have been impossible to guarantee the safety of the thousands of U.S. troops scheduled to deploy for the war game.
For the Pentagon, which had earlier delayed the delivery of four F-16 fighter jets to the Egyptian air force, other steps might be more difficult.
We need them for the Suez Canal, we need them for the peace treaty with Israel, we need them for the overflights, and we need them for the continued fight against violent extremists who are as much of a threat to Egypts transition to democracy as they are to American interests, said Gen. James Mattis, who retired earlier this year as head of the militarys Central Command.
While a cozy relationship with the Egyptian military might be preferable for U.S. interests to a radicalized, hostile government in Cairo, there is also a threshold of violence still unknown that, if passed, would make it impossible for the Defense Department to continue its dealings there.
As Egyptian generals familiar with the U.S. military are no doubt aware, there have been instances when the United States restricted or even severed military-to-military relations with a useful ally, for periods both long and short, because of authoritarian practices, human rights violations or security policies at odds with those of the United States. Among the examples are Indonesia, Pakistan and the Philippines.
But theres no mistaking Egypts importance, said Robert Springborg, a professor at the Naval Postgraduate School in Monterey, Calif., and an expert on the Egyptian military.
Springborg noted that in the run-up to the invasion of Iraq in 2003 after the Turkish Parliament refused to allow the U.S. military to use Turkish territory for crossing into Iraq from the north Egypt gave the Pentagon immediate access for two aircraft battle groups and accompanying aircraft through the Suez Canal and across its territory.
Given the number of countries in the region that do not allow U.S. military overflights, especially for combat missions, Egypts location makes it a vital, and relatively direct, access route to an unstable crescent of strategic importance.
Egypts role in the Camp David agreements has also been of critical value for Americas closest ally in the region, Israel. In the four decades before Camp David, Israel and Egypt fought several major wars; in the nearly four decades since, none.
Even in the current crisis, the military communications systems established by Camp David to link Israel and Egypt have helped defuse tensions. When Egypt recently moved additional troops into the Sinai Peninsula in violation of the accords Israel quietly assented, knowing that the extra forces were to secure the border and tamp down rising militant activities.