An American paratroop battalion being led by its commander Lt. Col. Garrison (with a cane) through the desert to take up peacekeeping duties between Israel and Egypt in Sharm el-Sheikh, Egypt on March 17, 1982. (Max Nash/AP)

A dramatic rise in militancy and violence in the vast Sinai desert is increasingly threatening a peacekeeping force there that includes nearly 700 U.S. troops acting as guarantors of a peace treaty between Egypt and Israel, according to Western military officials.

Heavily armed locals have blockaded bases and convoys, and, in a few instances, launched attacks against the peacekeepers, raising concerns about not only their safety but also the long-term stability of their mission. That mission had become more challenging even before the most recent phase of Egypt’s post-
revolution crisis, with regional volatility forcing members of the Multinational Force and Observers, many of whom operate out of remote bases, to bolster security and limit their movements.

“Right now, the situation is very volatile up here,” Col. Thomas O’Steen, the chief of staff of the peacekeeping force, said in a phone interview last week. “As you can imagine, the Egyptian security forces are struggling to maintain security. We are being very cautious and prudent in the routes we allow for our patrols and resupply convoys to minimize our exposure.”

The peacekeeping force, which relies heavily on the Egyptian government for security, is an integral part of the peace treaty, which has been at the heart of U.S. policy in the region since Egypt and Israel signed it in 1979. Keeping the coalition secure and viable has been among U.S. officials’ key — if largely unspoken — considerations as they have debated the pros and cons of shutting off or making conditional the $1.3 billion in military aid awarded annually to Cairo.

Some U.S. officials worry that a rupture in the relationship between Washington and Egypt’s generals could diminish the Cairo government’s willingness and ability to host and protect the force.

“All major strategic aspects of our relationship with Egypt are dependent on a highly cooperative relationship with the Egyptian military,” said Rep. Gerald E. Connolly (D-Va.), who has closely followed the evolution of U.S. policy on Egypt since he worked as a Senate staffer in the early 1980s. “Disruption of that cooperation would have implications for all of those. It’s a very complicated relationship that does not lend itself to facile policy determinations.”

‘On maximum alert’

The 13-nation peacekeeping force, which includes American, Colombian, Fijian and Uruguayan troops, operates out of two main bases and a network of 30 small outposts. Security around the southern Sinai base, which is close to Sharm el-Sheikh, a resort town, has been fairly stable.

But conditions around the northern camp have become increasingly dire. Militants have launched near-daily attacks on Egyptian security forces in the area, in a violent backlash to the ouster of President Mohamed Morsi. Last week, gunmen ambushed a convoy of Egyptian police recruits and executed 25 on the side of a road near a peacekeepers’ checkpoint.

“This demonstrates the virulence of violence in that area,” said Agustín Espinosa, the Uruguayan ambassador in Cairo. “This compels us to be on maximum alert.”

In response to the growing threat, the peacekeeping force has strengthened security at the ­bases, begun using armored SUVs and generously stocked remote outposts in case it becomes difficult to access them. A team from U.S. Central Command was recently dispatched to conduct a “vulnerability assessment” of the bases.

Commanders have also provided troops with specialized training on a range of nonlethal responses to attacks, fearing that a fatal confrontation could make local communities turn on the troops.

Under the terms of the Israel-Egypt treaty, the peacekeepers are not authorized to collect intelligence or conduct offensive operations. That means that they must rely on the Cairo government for information about the militant cells that have taken root along the Egyptian side of the border.

New Zealand Maj. Gen. Warren Whiting, the commander of the force, said in a statement that the peacekeeping coalition has maintained strong relationships with the Egyptian and Israeli governments despite the recent regional upheaval and continues to perform its mission.

“The MFO maintains close links with the Egyptian government in Cairo, and the Egyptian Army has placed a priority on maintaining communications with the MFO,” he said.

Challenges, close calls

The Sinai peacekeeping force and its challenges have gone largely unnoticed in recent years, in large part because it seeks to keep a low profile as a matter of policy. The force’s director general, veteran U.S. diplomat David M. Satterfield, who is based in Rome, declined an interview request.

Still, the force’s latest yearly report provides a detailed and sobering glimpse into the recent challenges and close calls that the peacekeepers have faced.

Since President Hosni Mubarak was ousted in January 2011, the report says, “the number of rock-throwing incidents, roadblocks, protests and overt surveillance of MFO positions (and in a few cases the display and use) of weapons has increased dramatically.”

In spring 2012, gunmen opened fire on a peacekeeping convoy during the course of a blockade of the force’s remote sites and convoys. The most worrisome incident occurred Sept. 14, when a “violent crowd” launched an attack on the northern camp using molotov cocktails, breaching the perimeter.

“Armed elements fired upon and ultimately destroyed a ballistically protected guard tower and threw an explosive device,” the report said. Eight members of the force suffered minor injuries in the attack, which was repelled by Colombian troops. The assault caused “significant damage,” including the destruction of a firetruck.

During Mubarak’s rule, militant attacks launched from the Sinai triggered a crushing response from Egyptian intelligence and military units, which raided homes to seize weapons and rounded up hundreds of Islamists. Since his ouster, the government has struggled to push back against the rising militancy because residents have stocked up on heavy weapons that streamed into the country after Libya’s 2011 civil war and because Egyptian troops have been spread thin dealing with urban unrest across the country.

That has allowed two particularly hard-line groups to launch attacks against Israel from the region. Israel is thought to have carried out a recent drone attack in response to rocket fire from the Sinai, the latest in a series of cross-border incidents that could strain Cairo’s relationship with Israel.

“Both groups aim to drag Israel to retaliate in Sinai, thus sabotaging Egyptian territory and authority,” said Aviv Oreg, a security analyst in Tel Aviv who once led the Israeli military’s intelligence division that tracks al-Qaeda and like-minded groups. So far, he said, attacks launched from the Sinai have been largely ineffective. “The big question is how much can Israel contain or bear,” Oreg added.

Israel and Egypt have developed a functional working relationship over the years, even as Egypt has deployed more troops to the Sinai than the original treaty authorized. Nonetheless, peacekeeping officials say it remains important to have a strong, independent actor on the ground.

“The most important thing we do is give confidence to both parties that the treaty is viable,” said O’Steen, the chief of staff for the peacekeeping force, who is also the commander of the U.S. contingent. “Both parties have a lot of confidence in the MFO as a neutral party.”