Trump-Russia Investigation and Facebook: Why Mueller's Counterintelligence Effort Is Just as Important as His Criminal Probe

The Trump-Russia investigation: Every day, we hear something new about Robert Mueller's criminal probe—from rumors of Kremlin-connected money laundering to questions about why the president fired former FBI Director James Comey. Considering how polarized this country is, it's understandable that much of the focus has centered on Mueller's criminal probe.

But as the special counsel investigates possible coordination between Moscow and the Trump team, he's not only looking at potential crimes. He's also overseeing a counterintelligence operation, delving into Russian meddling in the 2016 U.S. presidential election. It's this counterintelligence effort, not the criminal investigation, that will unravel why and how Moscow-connected groups spent at least $100,000 on Facebook ads during the campaign. Among other things.

Related: Is Trump really a Russian spy?

Criminal investigators can't thwart a foreign intelligence op or fix the gaps that allowed it go undetected. Both are the purview of the FBI's counterintelligence division. These folks don't necessarily need arrests to be successful. Take the 1989 case of Felix Bloch, a State Department officer suspected of being a Soviet spy. After attracting the attention of the FBI, the bureau's counterintelligence officers spotted him meeting a known Soviet agent in Paris with whom he left a bag. Before the FBI could close in, however, an FBI spy named Robert Hansen tipped off Bloch, saying he was under surveillance. When the bureau confronted him about his spying activities, Bloch claimed he was simply passing stamps to the Soviet agent. He was fired, but a case against him never materialized. The good news: Soviet agents never worked with him again, and that was a win for the bureau's counterintelligence officers.

For the FBI's criminal division, the outcome was a lot less favorable. That's why the two divisions are separate: One is a law enforcement agency, the other an intel shop. Law enforcement is interested in perp walks and courtroom presentations. Counterintelligence officers? Not so much. Stopping a foreign intelligence service is best done in secret. "The end goal for a prosecutor is to publicly present everything they've uncovered to a jury," says Vince Houghton, a historian and curator at the International Spy Museum in Washington, D.C. "But in counterintelligence, you'd never lay all of your cards out on the table—if you do, you're just letting your opponent gain the advantage."

Take my case, for example. When I worked for the bureau as a double agent, my handlers at first wanted me just to watch the Russians. Knowing what they were asking for showed them what Moscow's military needed, which helps U.S. intelligence. But there was no interest or desire to build a criminal case. (Later, when Russia showed interest in developing me into a spy, my handlers changed my role, making me an asset.)

In the Trump-Russia probe, Mueller's job is twofold: building a criminal case and investigating how the Russians meddled in the election. The criminal case may seem more important for those hoping Trump will be impeached. But if we really want to understand what happened—and how we can make sure Moscow never interferes in our election again—it's actually the counterintelligence part of the probe that's essential.

This part of the investigation may get fewer headlines, but it's just as important.

Naveed Jamali is the author of How to Catch a Russian Spy, a memoir about working undercover as a double agent for the FBI. He continues to serve as an intelligence officer in the United States Navy Reserve and a senior fellow in the Program on National Security at the Foreign Policy Research Institute. His views are his own.