Sam Clovis, a former national co-chairman of the Trump campaign, is one of three Trump figures known to have been contacted by FBI informant Stefan Halper during the 2016 presidential campaign. Clovis received an email, out of the blue, from Halper, whom he did not know, on August 29, 2016 — after Halper had been in touch with Carter Page and just before he contacted George Papadopoulos.

Page and Papadopoulos were peripheral, sometime volunteer Trump foreign policy advisers, but they are key figures in the investigation into whether the Trump campaign colluded with Russia to rig the 2016 election. Clovis, who is not suspected of any wrongdoing, has testified and been interviewed for a total of 19 hours, by his own count, before special counsel Robert Mueller's investigators, before Mueller's grand jury, and before the House and Senate intelligence committees.

During all that testifying, Clovis never knew about Halper's connection to the FBI. Only recently, from news reports, has Clovis learned about Halper's true role. And that has prompted Clovis to re-play his brief and seemingly inconsequential encounter with Halper in light of a wealth of new information.

It began with that August 29, 2016 email. Here is the complete text:

I am a professor at Cambridge University lecturing on US politics and foreign policy. I am what is called a 'scholar practitioner,' having served in the White House and four presidential campaigns -- two as policy director. Over the past month I have been in conversation with Carter Page who attended our conference in Cambridge on US elections. Carter mentioned in Cambridge, and when visiting here in Virginia, that you and I should meet. I have enjoyed your comments and appearances in the media; you hit the sweet spot focusing Trump's appeal to working America. May I suggest that we set a time to meet when you are next in Washington. Meanwhile, all the best, Stefan Halper.

Halper's note to Clovis — they worked out logistics and met at Clovis' hotel, the Doubletree Inn in Crystal City, Virginia, a couple of days later — was premised on his approach to Page. And it seemed of a piece with Halper's approach, the very next day, to Papadopoulos. But the actual content of their meeting has left Clovis wondering what Halper was up to.

He wasn't wondering at the time — Clovis thought the meeting was so inconsequential that he did not report it up the chain at the Trump campaign, as he would have done if he had met someone who might be important to the campaign or who might be seeking a job. Only now, after reports that Halper was an informant for the FBI, has Clovis mentally gone back over their meeting in an attempt to figure things out.

Halper mentioned only briefly, and in passing, that he had met with Page, Clovis recalled when we discussed the meeting recently. Instead, Halper stressed his academic research, mostly about China and trade.

"It was about China," Clovis said. "It had nothing to do with emails. No mention of Russia. No mention of Hillary Clinton. No mention of her campaign. Only a mention in passing that he had met with Carter Page. Other than that, it was a discussion of his research and what he thought about China."

"It was like two guys sitting in the faculty lounge talking," Clovis continued. "It was so innocuous I never reported it back to headquarters. It did not raise any antennas or red flags or something we needed to be on guard against."

I asked if Halper volunteered to work for the campaign, or asked to be part of it. "No, not at all," Clovis said. But: "He said he was willing to share the research if it would be useful to our foreign policy effort."

That soft offer to help was apparently consistent with what Halper did earlier with Page. It is always hard to discern the exact meaning of Page's statements, but Page has tweeted a line from an email he says he sent to the campaign on July 16, 2016, regarding Halper. Halper — Page referred to him as the professor — "offered a range of possibilities regarding how he and the University might be able to help," Page wrote.

Halper's behavior with Papadopoulos appears to have been quite different. Chuck Ross of the Daily Caller has reported that, "Sources familiar with Papadopoulos's version of their meetings said Halper randomly asked Papadopoulos whether he knew about Democratic National Committee emails that had been hacked and leaked by Russians."

Ross continued: "Papadopoulos strongly denied the allegation, sources familiar with his version of the exchange have told TheDCNF. Halper grew agitated and pressed Papadopoulos on the topic. Papadopoulos believes that Halper was recording him during some of their interactions, sources said."

That account could not be more different from Clovis's experience with Halper. So much so that Clovis believes Halper had very specific purposes in approaching the Trump figures he approached.

"This is just my speculation — I have no knowledge," Clovis told me. "I think [Halper] was using his meeting with me to give him bona fides to talk to George Papadopoulos. He used Carter Page to get to me and he used me to get to George. George was the target. I think George was the target all along."

Clovis's theory is that Halper was trying to link Papadopoulos and the 30,000-plus emails that Hillary Clinton unilaterally deleted from her private email system. Halper was hoping "that somebody would bite in the campaign … his goal was to drag George into this to say the Trump campaign tried to get access to those emails from Russia."

If that is what Halper was trying to do — and again, that is simply Clovis' theory — then it didn't work. "Nobody was biting," Clovis told me. "As far as I know, no one in the campaign lifted a finger to get to the 30,000 emails. I don't think it was in their interest. Anytime anybody approached me about oppo, I deleted it. Oppo research against Hillary Clinton? We had plenty of material. It's not like it's not a target-rich environment."

One obvious question from all of that is how investigators, in their questioning of key witnesses, handled Halper's role in the affair. Did they mention the FBI informant? Did the intelligence committees even know Halper was an FBI informant?

Clovis told me that in all 19 hours of questioning, no one — not Mueller's investigators, not investigators from the House or Senate, not anyone — ever mentioned Halper. (Clovis said that, among other documents, he gave all the investigators all emails making any reference to Carter Page, so he believes he turned the Halper email over.) At the time he was questioned, of course, Clovis did not know Halper was an FBI informant.

As for Page, he told me in an email exchange that he turned over "tons of personal documents that included many records of all my meetings." When I asked whether investigators had information about his dealings with Halper specifically, Page said, "They explicitly had documentation that allowed them to know that information of which you're enquiring."

But at least some on Capitol Hill weren't interested. There is a publicly-released transcript of Page's interview with the House Intelligence Committee, and the questioners showed no awareness of or interest in Halper. Page mentioned on a number of occasions that he had traveled to Cambridge University, and the lawmakers, including Democratic Rep. Adam Schiff, D-Calif., and Republican Rep. Mike Conaway, R-Texas, moved on to other topics.

For example, when Conaway questioned Page about who paid for his plane fare to give a speech in Moscow, Page said, "They bought me — they booked a ticket, just like Cambridge University booked a ticket for the — "

"Okay," said Conaway. "I don't need Cambridge; I just need the Russians."

At the time, it's fair to say that no one in the room knew that Halper was an FBI informant. It was only later that the House Committee's work led to the discovery of Halper's role. And of course, congressional investigators still don't know all that Halper did, or what interactions he had with officials in the Justice Department and perhaps elsewhere in former President Barack Obama's administration. Right now, everyone, even some of those most closely involved in events, is still trying to figure out what happened.