A bomb partially destroyed the U.S. Embassy in Beirut in 1983, killing and injuring scores of people.AFP/Getty Images
Sen. John McCain, R-Ariz., has called it a cover-up.
His fellow Republican Sen. James Inhofe of Oklahoma has compared it to the greatest of modern American scandals — the Pentagon Papers, Watergate, Iran-Contra.
However elected officials describe the Sept. 11, 2012, attack on the U.S. Special Mission in Benghazi, the story of what happened in Libya and why begins long before President Barack Obama took office.
In the discussion of Benghazi and diplomatic security, there are two constants: The threat to U.S. overseas missions has existed for decades, and security at many U.S. diplomatic posts is inadequate.
According to an Al Jazeera analysis of State Department data, U.S. diplomatic facilities and personnel were hit by 709 significant attacks from 1987 to 2012.
By year, the number of significant attacks on U.S. embassies and consulates and their personnel has ranged from as few as four in 1994 to as many as 83 in 2012.
Attacks on U.S. diplomatic posts began increasing significantly in 2008, largely because of stepped-up violence in Iraq and Afghanistan. But many attacks were launched in earlier years — 42 in 1988, for instance. Bottom line: U.S. embassies and other missions have been under siege for decades.
Indeed, an independent security panel report obtained by Al Jazeera underscores the dangers that diplomats face in overseas facilities.
For years, the State Department has established tough security regulations at U.S. diplomatic posts, then waiving those regulations when meeting them has been difficult or seemingly impossible.
The 1983 Beirut bombings of the U.S. Embassy and Marine barracks, which killed 338 people, show how security problems have gone unaddressed.
The attacks traumatized the nation so greatly that the State Department asked Bobby R. Inman, the former National Security Agency director, to review security at U.S. diplomatic posts and suggest policy changes.
Inman recommended that diplomatic facilities stand on properties of at least 15 acres and be set back at least 100 feet from surrounding streets, with blast-proof construction and no more than 15 percent of outside wall areas containing windows.
Within the State Department, the recommendations became known as the Inman standards.
However, since the State Department adopted the standards, agency officials from five presidential administrations have routinely waived the requirements for U.S. diplomatic facilities that do not meet them — including missions in high-threat regions.
In an interview with Al Jazeera on Monday, Inman, who now teaches at the University of Texas at Austin, said the State Department has a history of focusing on security for short periods and then ignoring safety issues "when the threat is not highly visible."
Inman described how "a large number of the career Foreign Service people were disdainful of security requirements." He added: "Security was not seen as something that enhanced your promotion opportunities to move towards being a career consular or ambassador."
Most startlingly, the U.S. Embassy in Beirut — whose destruction prompted Inman's inquiry — still does not meet the standards.
"That, to me, is appalling," he said. "If you are ever at a place where you are putting people who are representing us in that country at risk, it's Beirut."
State Department officials exempted Beirut from the Inman standards, just as they did for the U.S. Special Mission in Benghazi.
"If you are not prepared to invest for the level of security required, then you should close the facility," Inman said. "You should not leave people there exposed to be hostages or casualties while they are trying to do their job for the country."