President Donald Trump’s campaign wasn’t told of the FBI’s worries about Russian efforts to influence the 2016 election because such concerns had not “reached the point where it would be appropriate” to alert them, said James Clapper, the former director of national intelligence (DNI).

“The FBI has rules and protocols on when they decide to do things like that. And I don’t think at that point that it had reached the point where it would be appropriate to engage with the head of the campaign, or the nominee,” Clapper said Sunday morning on CNN’s “State of the Union.”

Clapper was responding to CNN’s Dana Bash, who asked him about complaints from Trump and his attorney, former New York City Mayor Rudy Giuliani, that the FBI didn’t notify Trump or his top campaign aides about Russia’s efforts to influence his campaign.

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“I want to ask you: One of the things that Rudy Giuliani brought up, and that the president has been tweeting about this weekend as well — which is if this was — if there was enough concern about people penetrating the Trump campaign, why not contact him?” Bash asked Clapper. “Why not contact the campaign, instead of sending an informant or a confidential source in? What’s the answer to that?”

Clapper replied, “Well, I think the first thing is [to] determine just what was going on.”

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The FBI, according to The New York Times, placed an informant, Professor Stefan Halper, inside Trump’s campaign early in the spring of 2016. Halper subsequently met with former Trump advisers Carter Page, George Papadopoulos and Sam Clovis during the campaign.

Trump directed the Department of Justice last week to investigate whether the Obama administration improperly “infiltrated or surveilled” his campaign for “political purposes.” The task quickly fell to the DOJ’s inspector general, Michael Horowitz.

If the FBI’s “concern” about the Russians “could be allayed,” then perhaps there was “no reason” to alert Trump or his campaign, Clapper suggested.

Trump tweeted Saturday on the issue, asking: “With Spies, or ‘Informants’ as the Democrats like to call them because it sounds less sinister (but it’s not), all over my campaign, even from a very early date, why didn’t the crooked highest levels of the FBI or ‘Justice’ contact me to tell me of the phony Russia problem?”

With Spies, or “Informants” as the Democrats like to call them because it sounds less sinister (but it’s not), all over my campaign, even from a very early date, why didn’t the crooked highest levels of the FBI or “Justice” contact me to tell me of the phony Russia problem? — Donald J. Trump (@realDonaldTrump) May 26, 2018

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When Bash asked Clapper if he knew about the operation at the time, Clapper replied, “Absolutely not.” Clapper’s comments are likely to intensify questions from Trump and congressional Republicans about the legitimacy of the FBI investigation.

If, as Clapper claimed, the reason for putting Halper in the Trump campaign was to determine if the FBI’s concerns about Russian interference were justified, then why did the bureau rely almost entirely on opposition research paid for by Democratic nominee Hillary Clinton to justify its application for a Foreign Intelligence Surveillance Act (FISA) warrant to monitor Page?

If no such evidence is gleaned by Halper, it suggests the possibility the FISA warrant was sought for reasons not linked to the Russian activities. Trump and congressional Republicans have argued for months that the purpose of the FBI investigation was to help Clinton win the election.

But Bash failed to press Clapper for details regarding the informant’s discoveries. Clapper also didn’t volunteer any information about the nature of the informant’s discoveries and whether or not the initial infiltration and further expansion of the FBI’s Trump campaign investigation ultimately were justified.

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The FBI relied heavily upon the infamous anti-Trump dossier compiled by former British spy Christopher Steele alleging collusion with Russia to renew surveillance warrants against Page. The dossier was funded by the Clinton campaign and the Democratic National Committee (DNC) she controlled.

Clapper wasn’t asked, and didn’t volunteer information, about whether the FBI’s informant discovered significantly compromising information about the Trump campaign’s dealings with Russians and whether the information was used in the FISA warrant applications.

When Bash asked Clapper about the Trump legal team’s request for a briefing from the FBI regarding the informant, Clapper insisted it wouldn’t be a “good idea at all” to grant it.

But Giuliani insisted during an interview on “Fox News Sunday” that the FBI should have reached out to Trump and his campaign. The failure to do so “completely taints” special counsel Robert Mueller’s probe, Giuliani claimed.

Giuliani said he no longer believes the Mueller probe is legitimate.

“The whole thing with this investigation that was going on, which we consider spying, was done before Mueller got involved. But it completely taints his investigation,” Giuliani said.

Giuliani also said during an interview on “State of the Union” on CNN that he no longer believes the Mueller probe is legitimate.

“I did when I came in, but now I see Spygate,” Giuliani said.

PoliZette writer Kathryn Blackhurst can be reached at [email protected]. Follow her on Twitter.