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The 5 Other U.S. Ambassadors Killed by Terrorists

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Getty Images

According to the State Department Office of the Historian, five U.S. ambassadors had been killed in the line of duty by terrorists prior to the killings of U.S. Ambassador to Libya J. Christopher Stevens and three embassy staffers on Tuesday. Here are their stories.

1. John Gordon Mein – August 28, 1968, Guatemala

Mein became the first U.S. ambassador to be assassinated while serving in office when Guatemalan terrorists ambushed his limousine after a political luncheon in Guatemala City. Following his death, it was reported that Guatemalan military officials had tried to supply Mein with guards, and one Guatemalan colonel went so far as to enact a mock ambush to make a point to Mein that he was too cavalier about his safety. According to the Washington Post, Mein was determined to show that Guatemala’s terrorists could not force Americans into armored shells, and he routinely ran errands with minimal security.

Born in Kentucky, Mein spent much of his childhood in Brazil, where his father was a Baptist missionary. He graduated from Georgetown, earned a law degree from George Washington and worked for five years at the Department of Agriculture before joining the State Department in 1941. After serving in Brazil, Italy, Norway, Indonesia and the Philippines, Mein was appointed ambassador to Guatemala under President Lyndon B. Johnson in 1965.

2. Cleo A. Noel Jr. – March 1, 1973, Sudan

Members of Black September, a faction of the Palestinian Liberation Organization, killed Noel after kidnapping him and nine other diplomats from a party at the Saudi Arabian embassy in Sudan. The terrorists offered to exchange Noel and the other hostages for the release of 60 Palestinian guerrillas held in Jordanian prisons, as well as Sirhan Sirhan, who was convicted of assassinating Sen. Robert F. Kennedy. Upon learning of these demands, President Richard Nixon said, “We will do everything we can to get them released, but we will not pay blackmail.” In addition to Noel, his outgoing deputy, George C. Moore, and a Belgian diplomat were killed.

Noel was born in Oklahoma City, grew up in Missouri and graduated from the University of Missouri, where he taught history for a year before joining the Navy. He did graduate work in history at Harvard after World War II and was hired by State Department personnel officer Lucille McHenry, who would become his wife. He spent time in Saudi Arabia and Sudan before he was sworn in as U.S. ambassador to Sudan on Dec. 8, 1973 1972.

3. Rodger P. Davies – August 19, 1974, Cyprus

Davies was standing in the central hall of the U.S. embassy in Cyprus when a bullet fired by a Greek Cypriote sniper from outside the building struck him in the chest. An embassy secretary, Antoinette Varnavas, was shot and killed after running to Davies’ aid, while Davies was pronounced dead upon arrival at a private clinic nearby. The shots were fired during an anti-American demonstration, which was spurred by the Greek Cypriotes’ recent defeat at the hands of Turkish forces. One of Davies’ goals was to establish a peace agreement between the two sides. Five suspects were arrested in 1977 following an extensive investigation. While homicide charges were dropped, two men were sentenced to five- and seven-year prison sentences later that year for their involvement in the demonstration.

Born in Berkeley, Calif., Davis graduated from the University of California in 1942 and entered the Foreign Service after serving in the army during World War II. Prior to being nominated as the U.S. ambassador to Cyprus in 1973, Davis had served as the Deputy Assistant Secretary of State for Near Eastern and South Asian Affairs. He arrived at his post in Cyprus less than one month before he was killed.

4. Francis E. Meloy, Jr. – June 16, 1976, Lebanon

Meloy, his economic aide, and his Lebanese chauffeur were kidnapped and murdered in Beirut by members of the Popular Front for the Liberation of Palestine, a faction of the PLO. The kidnapping occurred as Meloy’s vehicle was crossing the dividing line between Beirut’s Christian and Muslim sections. Twenty years later, Lebanon’s top appeals court acquitted two former Islamic guerrillas who were involved in the assassinations. Their cases fell within the scope of a 1991 amnesty law that covers crimes committed during the war.

Meloy was born in Washington, D.C., served in the Navy during World War II and later as the U.S. ambassador to the Dominican Republic and Guatemala. President Gerald Ford nominated Meloy as ambassador to Lebanon following the resignation of the ailing G. McMurtrie Godley in April 1976.

5. Adolph Dubs – February 14, 1979, Afghanistan

Dubs, who was appointed U.S. Ambassador to Afghanistan after a Soviet-aligned faction came to power there in 1978, was kidnapped by four armed militants from the opposition party posing as policemen. The militants demanded the release of their imprisoned leader and took Dubs to a room on the second floor of the Kabul Hotel, where he was killed during a rescue attempt.

A Chicago native, Dubs graduated from Beloit College in 1942, served in the Navy during World War II and later studied at Georgetown, Harvard and Washington University in St. Louis. He entered the Foreign Service in 1949 and was one of the first Foreign Service officers assigned to West Germany. He later worked in Liberia and Canada before learning Russian and being assigned to Moscow in 1961. Dubs soon became a specialist in Soviet affairs.

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iStock // Ekaterina Minaeva
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
May 21, 2017
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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Library of Congress
10 Facts About the Tomb of the Unknown Soldier
May 29, 2017
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Library of Congress

On Veterans Day, 1921, President Warren G. Harding presided over an interment ceremony at Arlington National Cemetery for an unknown soldier who died during World War I. Since then, three more soldiers have been added to the Tomb of the Unknowns (also known as the Tomb of the Unknown Soldier) memorial—and one has been disinterred. Below, a few things you might not know about the historic site and the rituals that surround it.


Wikimedia Commons // Public Domain

To ensure a truly random selection, four unknown soldiers were exhumed from four different WWI American cemeteries in France. U.S. Army Sgt. Edward F. Younger, who was wounded in combat and received the Distinguished Service Medal, was chosen to select a soldier for burial at the Tomb of the Unknowns in Arlington. After the four identical caskets were lined up for his inspection, Younger chose the third casket from the left by placing a spray of white roses on it. The chosen soldier was transported to the U.S. on the USS Olympia, while the other three were reburied at Meuse Argonne American Cemetery in France.


One had served in the European Theater and the other served in the Pacific Theater. The Navy’s only active-duty Medal of Honor recipient, Hospitalman 1st Class William R. Charette, chose one of the identical caskets to go on to Arlington. The other was given a burial at sea.


WikimediaCommons // Public Domain

The soldiers were disinterred from the National Cemetery of the Pacific in Hawaii. This time, Army Master Sgt. Ned Lyle was the one to choose the casket. Along with the unknown soldier from WWII, the unknown Korean War soldier lay in the Capitol Rotunda from May 28 to May 30, 1958.


Medal of Honor recipient U.S. Marine Corps Sgt. Maj. Allan Jay Kellogg, Jr., selected the Vietnam War representative during a ceremony at Pearl Harbor.


Wikipedia // Public Domain

Thanks to advances in mitochondrial DNA testing, scientists were eventually able to identify the remains of the Vietnam War soldier. On May 14, 1998, the remains were exhumed and tested, revealing the “unknown” soldier to be Air Force 1st Lt. Michael Joseph Blassie (pictured). Blassie was shot down near An Loc, Vietnam, in 1972. After his identification, Blassie’s family had him moved to Jefferson Barracks National Cemetery in St. Louis. Instead of adding another unknown soldier to the Vietnam War crypt, the crypt cover has been replaced with one bearing the inscription, “Honoring and Keeping Faith with America’s Missing Servicemen, 1958-1975.”


The Tomb was designed by architect Lorimer Rich and sculptor Thomas Hudson Jones, but the actual carving was done by the Piccirilli Brothers. Even if you don’t know them, you know their work: The brothers carved the 19-foot statue of Abraham Lincoln for the Lincoln Memorial, the lions outside of the New York Public Library, the Maine Monument in Central Park, the DuPont Circle Fountain in D.C., and much more.


Tomb Guards come from the 3rd U.S. Infantry Regiment "The Old Guard". Serving the U.S. since 1784, the Old Guard is the oldest active infantry unit in the military. They keep watch over the memorial every minute of every day, including when the cemetery is closed and in inclement weather.


Members of the Old Guard must apply for the position. If chosen, the applicant goes through an intense training period, in which they must pass tests on weapons, ceremonial steps, cadence, military bearing, uniform preparation, and orders. Although military members are known for their neat uniforms, it’s said that the Tomb Guards have the highest standards of them all. A knowledge test quizzes applicants on their memorization—including punctuation—of 35 pages on the history of the Tomb. Once they’re selected, Guards “walk the mat” in front of the Tomb for anywhere from 30 minutes to two hours, depending on the time of year and time of day. They work in 24-hour shifts, however, and when they aren’t walking the mat, they’re in the living quarters beneath it. This gives the sentinels time to complete training and prepare their uniforms, which can take up to eight hours.


The Tomb Guard badge is the least awarded badge in the Army, and the second least awarded badge in the overall military. (The first is the astronaut badge.) Tomb Guards are held to the highest standards of behavior, and can have their badge taken away for any action on or off duty that could bring disrespect to the Tomb. And that’s for the entire lifetime of the Tomb Guard, even well after his or her guarding duty is over. For the record, it seems that Tomb Guards are rarely female—only three women have held the post.


Everything the guards do is a series of 21, which alludes to the 21-gun salute. According to

The Sentinel does not execute an about face, rather they stop on the 21st step, then turn and face the Tomb for 21 seconds. They then turn to face back down the mat, change the weapon to the outside shoulder, mentally count off 21 seconds, then step off for another 21 step walk down the mat. They face the Tomb at each end of the 21 step walk for 21 seconds. The Sentinel then repeats this over and over until the Guard Change ceremony begins.