• Days before Russia attacked Ukraine, US Embassy personnel evacuated Kyiv and then the country.
  • To ensure the safety of diplomats in such situations, the State Department has one of the least known but most capable security agencies in the United States.

In the weeks and days leading up to the Russian invasion of Ukraine, many focused on the US Embassy in Kyiv and what it was doing to determine the likelihood of a Russian attack.

Although the US intelligence community had warned of an imminent Russian attack for weeks before the invasion, the US Embassy in kyiv was only evacuated days before Russian tanks rolled into Ukraine.

This is the harsh reality of diplomatic life. But to keep them safe, American diplomats have one of the least known but most capable law enforcement agencies in the country.

The diplomatic security service

Embassy of the Diplomatic Security Service Niamey Niger

A Diplomatic Security Service security officer, right, in blue plaid, and Nigerian security forces during a drill at a U.S. Embassy residence in Niamey, April 12, 2018.

US State Department


Established in 1916 as the Office of the Chief Special Agent, the Diplomatic Security Service is the law enforcement and security arm of the State Department. Joseph Nye was hired as the first Chief Special Agent in late 1917.

With approximately 2,500 active special agents, the Diplomatic Security Service has four missions: to protect U.S. diplomats, to investigate passport and visa fraud, to ensure the integrity of classified U.S. travel documents, and to perform security checks .

The organization has the largest global reach in federal law enforcement, with offices in 270 locations around the world and 29 US cities.

Each US diplomatic mission operates under a security program designed by the Diplomatic Security Service. These programs are reviewed and updated regularly to reflect changes in the field. All US embassies have a regional security officer who reports to the ambassador and is responsible for all security-related matters.

Additionally, Diplomatic Security Service special agents work with the U.S. military’s high-level special missions units.

Diplomatic Security Service terrorist aircraft

Diplomatic Security Service trainers simulate a terrorist incident on an airplane with U.S. Ambassador-designate to Czechoslovakia Shirley Temple Black, right, in 1988.

US State Department


Special operators from the Army’s Delta Force and the Navy’s Naval Special Warfare Development Group — formerly known as SEAL Team 6 — will often visit U.S. embassies and consulates around the world to review their security and develop hostage plans.

As a result, the United States Joint Special Operations Command, which is the national mission force, has detailed plans for every American diplomatic installation around the world.

The Diplomatic Security Service also protects the Secretary of State as well as high-ranking foreign dignitaries and officials who visit the United States on official business.

While US Marines are responsible for protecting US embassies, the Diplomatic Security Service is responsible for protecting people, especially when traveling to a foreign country. After the attack on the US consulate in Benghazi, Libya, three diplomatic security officials were ousted from the State Department.

Like the Secret Service, which protects the President and investigates certain financial crimes, the Diplomatic Security Service has other roles. One of the most important is conducting security background investigations for the State Department and other federal agencies. The service screens diplomats, civil servants and other employees to determine their suitability for obtaining a security clearance.

Diplomatic courier

A diplomatic courier looks at crates being loaded onto a plane in 2017.

Diplomatic Security Service


Another function of the Diplomatic Security Service is to ensure the integrity of classified US travel documents.

When a U.S. Embassy needs to send or receive classified or sensitive material, the Department of State uses “diplomatic pouches” – which can be any properly sealed and identified package or container – which are granted a legal protection against searches by foreign agents.

Any intelligence service worth its salt will try to intercept the diplomatic pouches and take a look at their contents. This is where the diplomatic couriers of the Diplomatic Security Service come in.

The approximately 100 special agents who are dedicated diplomatic couriers ensure the rapid delivery of classified and sensitive documents worldwide. They are trained and certified to protect diplomatic pouches using a variety of classified techniques.

Selection and training

Embassy of the State Department of Marines in Bucharest Romania

US Marines and State Department officers respond to an attempted security breach during a drill at the US Embassy in Bucharest, February 28, 2015.

US Marine Corps/Sgt. Ezra Ruano


To become a Diplomatic Security Service Special Agent, a candidate must be a U.S. citizen, be prepared to deploy overseas, be between the ages of 20 and 36, and pass a physical fitness exam. They must also have a four-year degree and obtain a top secret security clearance.

Those who are selected then face a nearly 60-week pipeline to turn them into special agents.

Those who pass the initial screening move on to the Basic Special Agent Course, an intensive 29-week screening and training program. Candidates then move on to a three-week orientation, followed by a 12-week Federal Law Enforcement course.

The pipeline concludes with 13 weeks of specialized training, including small unit tactics, tactical combat care, and operational planning.

Diplomatic Security Service Mobile Security Deployment Team

Members of the Mobile Security Deployment Team secure a street for a motorcade at a hotel in Manhattan, September 23, 2018.

US State Department


Experienced special agents may be assigned to Mobile Security Deployments, a specialized tactical organization tasked with responding on short notice to heightened threats or emergencies at home and abroad.

MSD officers also assess facility security, plan travel routes, and provide counterattack teams for the U.S. Secretary of State and foreign dignitaries.

The State Department moved most of its personnel and operations out of Ukraine in the days leading up to the Russian attack. Russia has pulled out of Kyiv and some US diplomats say it’s time to reopen the embassy there, but the Biden administration remains divided on the matter, reflecting security concerns in Ukraine and continued caution after the Benghazi attack, according to Politico.

When the State Department moves to re-establish this diplomatic presence, MSD teams from the Diplomatic Security Service will likely be among the first on the ground.

Stavros Atlamazoglou is a defense journalist specializing in special operations, a veteran of the Hellenic Army (national service with the 575th Marine Battalion and Army HQ) and a graduate of Johns Hopkins University.