A number of commentators have focused on the bumbling nature of those in and around the Trump campaign, concluding that their ignorance and naïveté militate against their ability to engage in a conspiracy. This is a misunderstanding of how the espionage game works. Intelligence services recruit plenty of gullible people. The responsibility for recruiting, training, exploiting, and protecting a clandestine operation lies on the side of the professional intelligence service: The spy service must translate the target’s potential willingness into a productive and secure relationship; the professional intelligence officer must slowly manipulate the relationship in an increasingly conspiratorial and secret direction, then help rationalize it for the target. The Cold War was littered with Kremlin spies the West failed to uncover in a timely manner because Western agents assumed they were too obvious, absurd, drunk, dim-witted, or low-level. Naive and ignorant people can get in too deep when manipulated by professionals.

Effective counterespionage is difficult and often unsatisfying, and takes time. Investigators are trying to uncover what a professional intelligence service is hiding, and success usually requires our own sources deep inside the enemy camp. As the saying goes, “It takes a mole to catch a mole.” Rarely can investigators and specialists develop enough evidence to uncover and indict spies without leads from overseas intelligence collectors, as the “evidence” is locked away in the files of the SVR. Unlike criminal investigations that close down when they are unable to prove that a crime has been committed, counterintelligence investigations can continue for years.

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Likewise, counterintelligence professionals know that criminal prosecution is rarely the best tool for neutralizing the enemy. Even when investigators and intelligence officers are confident they’ve uncovered a spy, it is not a given that the person will be prosecuted. Hundreds of Americans spied for the Soviet Union during World War II and the Cold War, and only a small handful were ever brought to trial. The government’s methods of uncovering spies and its need to protect its sources limit its ability to produce convictions.

To some, it may seem unfair that investigators would not drop their efforts even after Mueller concluded that he could not “establish that the Trump campaign coordinated with the Russian government in its election interference.” Trump clearly thinks he’s been vindicated; he spoke to Russian President Vladimir Putin on Friday and said on Twitter that they discussed the “Russia Hoax” in their “long and very good conversation.”

Nevertheless, counterintelligence professionals realize they don’t have the whole story and will continue to work behind the scenes, slowly uncovering the activity of hostile intelligence services. From experience, they understand that failure to prove Russian espionage does not mean it didn’t happen. While the notion of “innocent until proven guilty” is something Americans take as solemn truth, to the Russian intelligence services it is just another vulnerability worth exploiting.

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