Why it’s so hard to prove that Russia was behind the election hacks

Cynics will understandably decry any call from intelligence agencies to “just trust us,” especially given that U.S. intelligence agencies have not always gotten it right. In this era of unprecedented sharing on the Internet, the idea of providing intelligence only to senior government policymakers can also seem dated. These concerns are a normal and healthy part of our democracy. Even though I worked hard in the past to protect CIA human sources and other methods, I do not begrudge those who call for investigations and transparency. It helps keep everyone honest.

But here is the reality: Human sources overseas understand viscerally the risks involved in stealing secrets and passing them clandestinely to the U.S. government. They are also highly sensitive to current events, given today’s interconnected world. Sources will tell their case officers, “I know you will want to use the information I have, but to do so will put me at great risk. Can you guarantee that you and your organization will protect me?” If they sense there is no such guarantee — or worse, if there are examples of when such guarantees were useless — they will self-edit. Sometimes they will simply refuse to report. Similarly, if technical collection methodologies are made public, the adversary — in this case, Russia — will take quick action to cut off the technical accesses gained after years of careful work.

In both cases, the flow of intelligence simply ends, and future collection can be seriously limited. New sources have to be recruited; new technical operations have to be undertaken. It takes years and is expensive, which is why the government uses intelligence collection as a last resort when attempting to obtain information abroad. Collecting information overtly, such as when the State Department uses its officers for official contact with foreign governments, carries less risk and less expense.