John Sipher, who spent 28 years as a CIA intelligence officer, explains that Russia's 2016 election interference tactics are nothing new, and he would be surprised if the Russians didn't have inside help:
Active measures are asymmetric political actions meant to influence an adversary – the art of having your enemy think what you want him to think.
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Political influence involves using spies and cooperative contacts to directly promote Russian interests inside adversary countries. These individuals secretly working on behalf of Russia are called “agents of influence.” It is not clear if the Russians secured spies inside the Trump campaign, but they certainly tried.
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As former CIA and NSA Director Michael Hayden commented in a recent “Atlantic” article, “covert influence campaigns don’t create divisions on the ground, they amplify them.”
In 2016, the dysfunctional U.S. political environment was dry tinder for the Russians. A single match led to a wildfire.
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Were the Russians aided by collaborators inside or around the Trump campaign, or inside our social media companies? We don’t know. If not, it would be a rare covert campaign that did not leverage human sources.
Full read: Russian Active Measures and the 2016 Election Hack (The Cipher Brief)