The question of why Obama was so focused on Flynn is especially revealing now. The Department of Justice recently filed to withdraw charges against the retired three-star general for making false statements to the FBI in a Jan. 24, 2017, interview regarding a phone call with a Russian diplomat. The circumstances surrounding the call and subsequent FBI interview have given rise to a vast conspiracy theory that was weaponized to imprison a decorated war hero and a strategic thinker whose battlefield innovations saved countless American lives. There is no evidence that Flynn “colluded” with Russia, and the evidence that Flynn did not make false statements to the FBI has been buried by the bureau, including current Director Christopher Wray.

So if the Obama administration wasn’t alarmed by Flynn’s nonexistent ties to Russia, why was he Obama’s No. 1 target? Why were officials from the previous administration intercepting his phone calls with the Russian ambassador?

The answer is that Obama saw Flynn as a signal threat to his legacy, which was rooted in his July 2015 nuclear agreement with Iran—the Joint Comprehensive Plan of Action (JCPOA). Flynn had said long before he signed on with the Trump campaign that it was a catastrophe to realign American interests with those of a terror state. And now that the candidate he’d advised was the new president-elect, Flynn was in a position to help undo the deal. To stop Flynn, the outgoing White House ran the same offense it used to sell the Iran deal—they smeared Flynn through the press as an agent of a foreign power, spied on him, and leaked classified intercepts of his conversations to reliable echo chamber allies.

In March 2017, after seeing evidence of the Obama administration’s surveillance of Trump associates, Congressman Devin Nunes said it had nothing to do with Russia or the FBI’s ongoing Russia investigation, or similar Russia probes conducted by congressional committees. Nunes’ contention was difficult to make sense of at the time. Wasn’t everything about Russia and whether or not there was, as Congressman Adam Schiff said, more than circumstantial evidence of collusion?

In fact, as Trump prepared to take office after his 2016 upset victory, the Obama White House was focused on the Middle East. “Russia collusion” was the narrative that Hillary Clinton operatives seeded in the media and fed to the FBI to obtain a warrant to spy on the Trump campaign. After the election, the Obama team took it over and used it to hobble the incoming administration.

That Obama has publicly criticized the Justice Department’s decision to withdraw its case against the retired general shows how personal the anti-Flynn campaign still is for the former president. In leaking his supposedly off-hand comments to Michael Isikoff, a journalist whose work was central in pushing the Trump-Russia collusion conspiracy theory, Obama was effectively taking credit for pushing the larger anti-Trump operation that grew out of the anti-Flynn campaign. While the Russia collusion story was a handy instrument for many to advance all manner of personal and political interests, for Obama the purpose of Russiagate was simple and direct: to protect the Iran deal, and secure his legacy.