Trump's national security adviser claims Iran more likely to negotiate now

White House national security adviser Robert O'Brien tells Axios that despite predictions to the contrary, he's convinced Iran is more likely to return to the negotiating table since the U.S. killed Quds Force leader Qasem Soleimani.

What he's saying: The strike will "reset deterrence," O'Brien added.

O'Brien sat down with Margaret Talev, Jonathan Swan and Alayna Treene at the Eisenhower Executive Office Building on Friday to talk about Iran and other national security challenges at the start of a new year.

• On the prospects for diplomacy with Iran, O'Brien told us: "I think the chances of sitting down with the Iranians and getting to a deal have improved significantly" because Soleimani's "off the battlefield."
• We'll have more from the broader conversation on Sunday evening in Sneak Peek.

Between the lines: O'Brien's claim flies in the face of what the Iranian leadership and regional experts are saying.

• Iran's UN ambassador described U.S. diplomatic overtures this week as "unbelievable," in light of the Trump administration killing Soleimani — which Iran's leaders view as an act of war. The Trump administration also added more sanctions against Iran Friday.

O'Brien said he thinks "the Iranians have realized they don't want a military confrontation with the U.S. and that the maximum pressure campaign is not going to end."

• "Soleimani's belief was he could end the maximum pressure campaign by going up an escalation ladder with the U.S., taking out drones, taking out Saudi refineries, taking ships and that sort of thing," O'Brien added.
• "I think those plays are over now. ... I believe that the Iranians are standing down," O'Brien said.

After hotly denying it and blaming a mechanical problem, Iran today took responsibility for the fatal crash of a Ukrainian jet over Iran, saying it was an accident by the Revolutionary Guard.

• O'Brien, speaking before that admission, said if it was a mistake by their armed forces, Iran must provide compensation to victims' families and allow a "full and impartial" investigation.

O'Brien described a president who was determined to project strength as he saw pro-Iranian crowds attack the U.S. Embassy in Baghdad.

• At Trump's direction, O'Brien said, the U.S. brought in a Marine Corps company and Army infantry platoon: "We got air assets, Apaches, up in the air, very quickly so that the crowd understood that this embassy was not going to be overrun. We were not going to have Tehran 1979. We weren't going to have Benghazi."
• "In the context of this, we received very strong intelligence that Soleimani was coming to the region to meet with his proxy allies, not just in Baghdad but Damascus and Beirut" to plan attacks against Americans.
• "We believed that if we took him off the battlefield that we could disrupt the attacks that were being planned against the United States."

Gulf allies to the U.S. can feel assured, O'Brien said, that "the U.S. is there to deter" Iranian aggression and "the Iranians understand that we mean business" and they should "think very carefully about attacking the United States and its interests in the region."

• He stopped short of any absolute guarantees, saying he wasn't going to negotiate defense treaties through an interview.

We asked O'Brien why the Trump administration publicly took credit for killing Soleimani, rather than killing him anonymously and leaving a "zone of deniability" — which some analysts have argued would have been more prudent because it would have been less humiliating to Iran's leaders. His response:

• "There weren't too many countries with the capability of undertaking that attack."
• Soleimani "was involved in plotting attacks against Americans at the time" and "we were going to disrupt those attacks. It would have become public."
• "There was no reason not to own it."

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