Every so often we hear about a big espionage case in which someone has been caught spying in the United States. Robert Hanssen, a former FBI agent, and Aldrich Ames, a former CIA employee, both gave secrets to the Russians. Then there were the 10 Russian spies caught in 2010.

Each time it seems we are still a bit startled. But it goes on more than we know.

I lost a friend recently who knew better than most about such issues. Brian Kelley — a former CIA counterintelligence officer, Air Force counterintelligence officer and official at the National Counterintelligence Executive — died last week. He was a hero, an honorable man who was awarded the Distinguished Career Intelligence Medal.

Counterintelligence is what quiet professionals like Brian do every day to protect us. He sacrificed much during his service, then became an educator at CIA University and the Institute of World Politics. He was passionate about his work and an example for those who are interested in “spy catcher” careers. There are several agencies to consider. Too many to list here. But here are a few:

The CIA, which has counterintelligence analysts and officers. cia.gov/careers.

The Defense Intelligence Agency absorbed the Counterintelligence Field Activity. This office is known as the DX: Defense Counterintelligence and HUMINT Center. dia.mil.

The FBI. fbi.gov/about-us/investigate/counterintelligence.

The Naval Criminal Investigative Service. You may have seen the television show where members investigate murders, but they also are in the counterintelligence field. ncis.navy.mil.

The Army’s Intelligence and Security Command, whose 902nd Military Intelligence Group focuses on counterintelligence. And the Army’s Criminal Investigation Division. inscom.army.mil and cid.army.mil.

The Air Force has the Office of Special Investigations. Its mission is to identify, exploit and neutralize criminal, terrorist and intelligence threats to the Air Force, Defense Department and U.S. government. osi.andrews.af.mil.

Also, there’s the Defense Security Service, which identifies unlawful penetrators of the U.S. defense industry. dss.mil.

The Energy Department deals with nuclear energy and other scientific national security matters and has the Office of Intelligence and Counterintelligence. One example is its Richland Field Office at its Hanford site. hanford.gov/page.cfm/oci.

The National Counterintelligence Executive’s mission is to be the unifying agency of the U.S. counterintelligence community. ncix.gov.

There are many other opportunities not listed here. These folks rarely receive public recognition, but it’s the Brian Kelleys across the country who we must thank for helping to keep us safe.

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