They are a mixture of Green Berets, Rangers and the Delta Force from the Army, the Seals (which stands for Sea-Air-Land) from the Navy and the Air Force's combat controllers and para rescue teams.

BBC: Snipers

The report alleged widespread misappropriation of aid and the use of forced labour by the army in the delta.

ECONOMIST: Myanamar after the cyclone

The U.S. Army created the Delta Force in 1977 to respond globally to terrorist attacks, including those similar to the Benghazi attack.

CENTERFORSECURITYPOLICY: benghazi-congress-letter

He worried the troops would reject him because he had not served in any of its elite units such as the Army's Delta Force or the Navy's SEAL Team 6.

NPR: McChrystal Takes Blame For Rolling Stone Article

It will be up to the military service chiefs to recommend whether women should be excluded from more demanding and deadly positions, such as Navy SEALs or the Army's Delta Force.

WSJ: Women in combat face doubts over emotions, ability

Perhaps if you had absolutely no knowledge of the U.S. military, or indeed access to Wikipedia where SEAL Team Six has had an entry since 2004, it would be news to you that SEAL Team Six, along with the Army's Delta Force, are America's premier counterterrorism units.

CNN: Are 'Swift Boat' attacks on Obama bogus?

Kirkpatrick's article went to press, moreover, it became apparent that even the employment of those "crack troops" -- U.S. Army Ranger and Delta Force units in Mogadishu -- is of a piece with this approach: Thanks in no small measure to the abysmal "operational security" that has come to characterize the U.N.

CENTERFORSECURITYPOLICY: Center For Security Policy

James Vaught, a retired lieutenant general who helped create the Army's elite Delta Force, disapproves of the SEALs' participation.

WSJ: A Navy SEAL on an Unusual Mission: An Acting Role in 'Act of Valor'

Besides the furore over tear gas, the Justice Department and Pentagon must also answer allegations that an army Special Forces unit, Delta Force, was actively involved in the Waco raid.

ECONOMIST: Government evasion