As Friday prayers came to an end on Jan. 28, 2011, the sound of chanting echoed through the streets of Cairo. “Ya ahalaino endammo leena!” the voices called. “Oh, people, join us!” It was three days since protests against President Hosni Mubarak’s government first erupted across Egypt and the first day of the weekend, allowing for more people to take to the streets. The Mubarak regime had cut off Internet and cell phone service. Members of the Muslim Brotherhood had been detained. An evening curfew had been declared.

Mohamed ElGohary, then a 25-year-old activist and blogger, had just returned to his apartment in El Hussein, a neighborhood a couple miles north of Tahrir Square, when he heard the chanting. A pudgy, gregarious fellow, ElGohary looks a bit like an Egyptian version of Seth Rogen. He sports rectangular, tortoiseshell glasses, has curly dark brown hair, and has a weakness for flaky baklava. It was a brisk winter day, and ElGohary threw on a jacket and stuffed a wad of Egyptian pounds into his shoe just in case he was detained by the police.

Outside, he met up with a group of a hundred protesters, and for the next six hours they zigzagged through Cairo’s chaotic streets, making their way toward Tahrir, where the protests were centered. The police were out in full force with their navy uniforms and rifles, standing menacingly atop parked vehicles. Then it happened: ElGohary heard the crack and hiss of a tear gas grenade landing on the ground nearby. White smoke poured out of the canister and filled the air. He started coughing and shuddering. He fled into an alley and doused his face and eyes with Pepsi, which Tunisian friends who’d helped overthrow their own government two weeks earlier had told him inactivates the noxious chemical. But the tear gas kept coming. “The feeling was suffocating,” he would recall. “I wasn’t able to see properly. I was barely able to breathe.”

As the revolution wore on, ElGohary came to expect this chemically induced agony with every outing. Sometimes the gas was smoky, opaque, and easy to evade. Other times it was invisible. On the streets, he regularly saw people bleeding from their noses. Others were so worn out from the struggle that they would collapse in their beds. Police sometimes fired metal tear gas canisters directly at people. For days on end, an ominous yellow haze hung in the air above Cairo like Los Angeles smog.

By November, Mubarak had resigned and the military had been in control of the country for nine months, with no indication of when elections for a new president might be held. The people marched to the Square once again to show their displeasure, and tear gas filled the air. One night, ElGohary’s friend, a journalist named Mohammed Maree, thought he was going to die. For several perilous minutes, he was trapped in one of those invisible clouds and couldn’t force his lungs to inhale. Afterward, he and some friends collected the spent canisters on the street and read the blue words printed on the label: “Made in USA.”

Like many Egyptians, he felt a deep sense of betrayal. How could the U.S., which had itself thrown off the shackles of tyranny, and whose leaders routinely expound on the ideals of political freedom and free expression, support the regime's oppression of peaceful dissent? “The United States only thinks about their interests, regardless of what the people of the world suffer from,” Maree told me. “They don’t care about anything.”

An Egyptian protester holds a canister during clashes with Egyptian riot police in Cairo on Nov. 21, 2011. (Photo: STR/Associated Press)

For more than a century, police and military around the world have embraced tear gas as a humane approach to quelling rowdy demonstrations. Strictly speaking, tear gas is not a gas but a cloud of liquid droplets or a powder, propelled into the air by igniting fuel. Various tear gases, or lacrimatory agents, as scientists call them, have been known since the late 1800s. The most common tear gas used in Egypt today, 2-chlorobenzalmalononitrile, or CS, was named after the two chemists who developed it at Middlebury College in Vermont in the 1920s. Benjamin Corson and Roger Stoughton were experimenting with so-called dinitrile compounds when they were hit with a “peppery sting.” “They are harmless when wet but to handle the dry powder is disastrous,” they wrote in a 1928 paper. With one substance, they wrote, “mucous discharge from the nose becomes bright yellow on exposure to the air,” and another caused the face to “smart.”

Tear gases were first used by France, against criminals and, during the First World War, German soldiers. It wasn’t long before police in the United States saw their utility in combating labor riots. On Aug. 16, 1919, A.D. Porter of the New York Police Department wrote a letter to the head of the U.S. Army’s Chemical Warfare Service (now known as the Army Chemical Corps), inquiring about the availability of the gases. “I am writing you on the subject of the use of tear gases in connection with crowds of strikers and disorderly persons on the street during the time of riot or other such disturbances,” he wrote. “Will you please be good enough to advise your opinion on the subject—i.e. as to whether it would be practicable, whether there would likely be any serious or lasting results to the people gased and whether in your opinion public opinion would tolerate the use of it?”

“We haven’t seen any real, concrete proof that the Egyptian authorities were misusing tear gas.” Mark Toner, State Department spokesperson

The Chemical Warfare Service quickly went to work developing a civilian tear gas grenade that would not explode and fragment like those used in combat, but the U.S. War Department forbade its use against the country’s own citizens. The man who led the tear gas effort for the CWS, Stephen DeLanoy, founded his own company, called Chemical Protection, to market the gas. On July 19, 1921, he staged a demonstration of the grenades for the Philadelphia Police Department. According to The New York Times, six of the “huskiest” officers were ordered to capture six others who were armed with 150 tear gas bombs. “Three times they charged but each time were driven back, weeping violently as they came within range of the charged vapor,” the paper reported. DeLanoy warned the men that the gas was “absolutely not dangerous” and “merely a tear-producing, choking nauseating gas.” But, he added helpfully, “be careful you don’t swallow too much.”

Used properly, in an open space with adequate circulation, the risks posed by tear gas are likely to be minimal, though long-term toxicological studies have never been conducted. “There’s very little published,” says Sven-Eric Jordt, a pharmacologist at Yale University. “There are isolated reports of injuries or lethality in persons who have preexisting conditions such as asthma.” His research has shown that tear gas acts directly on pain-sensing nerves in the cornea of the eye, the nasal passageways, and the upper airways, leading to mucous secretion, blockage of the airways, and shutting of the eyes. It can also cause severe skin burns. He believes that long-term exposure to tear gas, as with cigarette smoke or smog, could induce scarring. “Saying that tear gas makes you cry sounds harmless,” he says. “Tear gas is a nerve gas that targets pain-sensing nerves, and that way of thinking should trigger us to evaluate the use of tear gas.”

By 1923, more than 600 cities had adopted the use of tear gas, deploying it in prisons and insane asylums, against barricaded criminals and angry mobs. The shift of a military technology to civilian hands was complete. Although tear gas would be “prohibited as a method of warfare” in 1993 under the Chemical Weapons Convention, governments were still allowed to manufacture it and use it against their own people with little or no oversight. But it has never been more used more visibly—or with deadlier consequences—than during the Arab Spring. In the last three years, Amnesty International has documented Egyptian police targeting nonviolent protesters and firing tear gas canisters directly at field hospitals in Cairo and Suez. The Guardian has reported on claims that police were using a more dangerous form of tear gas that can cause seizures and unconsciousness and were making use of expired stockpiles of tear gas as much as a decade old. Events in Egypt have made it clear that tear gas is not a tool for ensuring public safety but for preventing political change at any cost. “The only time serious change has taken place in Egypt is when millions of people went to the streets,” says Shana Marshall, a political scientist at the Institute for Middle East Studies at George Washington University. “If they can keep people out of the streets, they can govern as they wish.”

Protesters run following detonation of a tear gas grenade fired by riot police during clashes along Qasr Al Nil bridge, leading to Tahrir Square, in Cairo on Jan. 27, 2013. (Photo: Mohamed Abd El Ghany/Reuters)

In the midst of the protests in November 2011—following reports that tear gas used against protesters bore the “Made in USA” stamp—the U.S. Embassy in Cairo condemned the use of “excessive force” and tweeted that “U.S. security assistance funds were not used for tear gas. That’s a genuine fact.”

Although it was strictly true that none of the $1.3 billion in military aid that the U.S. provides to Egypt each year went to the purchase of tear gas—that money gets earmarked for larger defense contracts for Apache helicopters, F-16 fighter jets, and Humvees—the U.S. government nonetheless has a critical role in approving the purchase and export of tear gas and other small arms.

One path that U.S. tear gas has taken to Tahrir Square begins in the hamlet of Jamestown, Pa., which bills itself as the “Gateway to Pymatuning,” a U-shaped reservoir famous for its walleye fishing and named after an Indian chief who lived in the area when the first European settlers arrived. If you drive a few minutes south of the lake and hook a right on Kinsman Road, you’ll see a complex of sheet-metal buildings nestled between farmland and a wooded stream. An American flag and an Israeli flag wave in the wind just beyond a sign for Combined Tactical Systems Inc., a subsidiary of Combined Systems Inc.

A shipping manifest obtained by the Egypt Independent for tear gas sold by Combined Systems Inc. of Pennsylvania to Egypt's Ministry of Interior. The text at bottom right reads, "These commodities are authorized by the U.S. Government for the export only to EGYPT for use by EGYPT MINISTRY OF INTERIOR."

Founded in 1981 by Jacob Kravel and Michael Brunn, Combined Systems Inc. considers itself the premier engineering and supply company for “tactical munitions and crowd control devices.” In addition to tear gas, Kravel and Brunn have designed many “low lethality” devices, including flash-bang grenades, rubber bullets, and handheld pepper spray. Some of their tear gas products are designed to be flung like grenades. Others can penetrate windows and walls and be loaded a dozen at a time into special launchers with rotating drums. CSI’s catalog, available in English and in Arabic, promises “a full line of chemical irritant and smoke munitions” for “aiding riot control units charged with maintaining order.” (Combined Systems Inc. did not respond to requests for comment.)

CSI is just one of three western Pennsylvania companies (along with Nonlethal Technologies in Homer and the now-defunct Federal Laboratories in Pittsburgh) whose canisters have been photographed by Egyptian protesters, bloggers, and journalists. In 2011, the company made at least three shipments to Egypt through ports in Wilmington, Del.; Sunny Point, N.C.; and New York City, according to documents obtained by Amnesty International. Only with the approval of the Directorate of Defense Trade Controls at the State Department can U.S. companies export tear gas and other small arms. The State Department is supposed to review a country’s human rights record each year, but Egypt, long considered a key ally in its support for Israel and the fight against terrorism, has never been restricted. “We haven’t seen any real, concrete proof that the Egyptian authorities were misusing tear gas,” State Department spokesperson Mark Toner said at a briefing in late 2011. He added, “Any kind of misuse...has the potential to jeopardize future exports.”

The U.S. is the world’s leading arms supplier, accounting for 30 percent of shipments, according to the Stockholm International Peace Research Institute. Combined Systems Inc. and other small arms manufacturers in Pennsylvania represent a small slice of that total, but they have a booster in Congressman Mike Kelly, whose district includes Jamestown, and who has been a vocal opponent of the United Nations Arms Trade Treaty, which the Obama administration signed in September. The ATT seeks to “prevent human rights abusers and violators of the law of war from being supplied with arms.” In December, the “Kelly amendment” passed as part of the 2014 National Defense Authorization Act, banning the Department of Defense from implementing the treaty. “As I and many others have long stated, the ATT is a clear threat to our national sovereignty and the Constitutional rights of Americans and should never have been signed,” Kelly indicated in a statement.

An Egyptian protester sprays water on the eyes of a fellow demonstrator after tear gas was fired by security forces on the third day of clashes at Tahrir Square in Cairo on Nov. 21, 2011. (Photo: Mohammed Hossam/AFP/Getty Images)

The consequences of inaction have been clear: Over the last three years, the widespread use of tear gas in Egypt and the Middle East has caused gruesome injuries and deaths. In January, a tear gas grenade fired by the Israel Defense Forces landed inside the West Bank home of an 85-year-old Palestinian, and he died in a hospital the following day. Physicians for Human Rights has called the use of tear gas against protesters in Bahrain “unprecedented” and an egregious violation of human rights that has led to 39 deaths. The group wrote in a report last fall that in Turkey, the government used more than 130,000 tear gas canisters during protests in 2013; PHR met three people who lost an eye after being hit by the canisters. “In the last 10 to 20 years, tear gas has been used increasingly not simply for riot control but in a punitive way to target people who are considered in opposition to the current regime,” says Dr. Vincent Iacopino, who worked on the report. “There is no reason on earth to fire tear gas at peaceful protesters.”

Activists have made limited progress in interrupting the tear gas pipeline that feeds these repressive regimes. In 2013, the Campaign Against Arms Trade, Americans for Democracy and Human Rights in Bahrain, and Bahrain Watch launched a campaign called “Stop the Shipment” to prevent South Korea from shipping some 3 million tear gas shells to Bahrain. In early January, the South Korean government halted shipments owing to the reported deaths and injuries and “complaints from human rights groups.” In a statement, Bahrain’s Ministry of Interior responded that tear gas was “used entirely in compliance with international law” and not against peaceful gatherings, only “riot control situations.”

Tear gas shipments in Egypt, however, have continued, sometimes with devastating results. Following Mubarak’s departure, the military and various political factions vied for control of the country in a bitter struggle. In June 2012, Mohammed Morsi of the Muslim Brotherhood was elected president, but he was ousted by the military one year later. Since then, an estimated 10,000 members of the Muslim Brotherhood have been detained and 1,000 have died during protests and skirmishes in the streets. The United States cut back on military aid but refused to call the power shift a coup, which would have forced it to cease aid. “Anyone who opposes the government is now called a terrorist,” says the blogger ElGohary, who likens the situation to a witch hunt, in which activists are persecuted and jailed simply because an opponent points a finger in their direction. “The U.S. has lost its ability to communicate with the Egyptian government. U.S. aid goes to American companies supporting their economy rather than pushing the Egyptian government.”

In the months leading up to Morsi’s ouster, Combined Systems Inc. shipped a $2.4 million order to Egypt’s government, including 70,000 grenades and 70,000 long-range cartridges, according to a shipping manifest acquired by Egypt Independent. On Aug. 18, after one of the bloodiest days of clashes between Morsi supporters and security forces, policemen packed 45 detainees into a bus meant to carry half that many. Officers allegedly fired tear gas into the vehicle, killing 37 of the detainees. At first the Ministry of Interior claimed that the deaths occurred during an escape attempt, but it has since backpedaled, and the prosecutor general has ordered four senior officers to stand trial. Whatever the outcome of the trial, one thing will never change. “The problem in Egypt,” ElGohary says, “is you can use any kind of weapon as a lethal weapon.”

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