JD Vance was scheduled to spend the week promoting his new book, the kind of event a potential presidential candidate like the vice president typically uses to speak to a wide audience about his life and values ahead of a campaign.

Instead, the rollout of Vance's second book, "Communion: Finding My Way Back to Faith," has had to share focus with something else he's put his name on: the deal to end the Iran war.

The Republican vice president has embraced the role of chief defender of the agreement he and President Donald Trump signed with Tehran, giving a series of interviews touting it as a success, releasing a video championing it and parrying questions about it during a briefing at the White House.

It's a striking emergence for a politician who has in the past expressed skepticism of foreign military interventions.

Vance has been critical of expansive U.S. military interventions, frequently citing the Iraq and Afghanistan wars as examples of strategic overreach and arguing that American commitments abroad should be more narrowly defined with clear objectives.

In the Senate, he questioned Ukraine supplemental funding packages, arguing that European allies should take on a greater share of the burden and that U.S. support risks becoming open-ended.

He has framed that approach as part of a broader foreign policy of restraint, favoring diplomacy and limited engagements.

Next phases

The vice president is poised to link himself further to the conflict's outcome with a major role in the next phase of negotiations with Iran — though when that will occur was still up in the air Thursday.

In one sense, the role of hype man for the deal could benefit Vance in the next presidential election. The war has been divisive, and voters could reward him in a big way for being the face of ending the conflict. 

But there may also be risks if the deal falters. Trump himself joked about such a possibility Wednesday.

"If it works out, I'm going to take the credit," Trump said. "If it doesn't work out, I'm blaming JD."

Vance on Thursday referred to Trump's comment as a joke and said he wasn't worried. He added: "Look, the entire team has worked very well on this, and we've got this thing to a very good place for the American people."

The White House in a statement called Vance the president's "right-hand man and an invaluable member of the President's talented national security team."

"That's why the Vice President was trusted to lead these negotiations alongside Special Envoy Steve Witkoff and Jared Kushner," White House spokeswoman Olivia Wales said. "What President Trump and his team achieved on the battlefield and at the negotiating table is nothing short of remarkable and will strengthen American security for years to come."

Must meet obligations

As details of the agreement have emerged, some conservative pundits and Republican lawmakers have expressed reservations about some of its terms. (The deal was signed electronically Wednesday and released to journalists Thursday.)

Among the issues: concerns that the deal, meant to open a two-month negotiating period, seemed to offer Iran wins up front while guaranteeing little in return, and worries that the administration's stated reason for launching the conflict, to prevent Iran from obtaining a nuclear weapon, remains unsettled as of now.

Vance spokesman Luke Schroeder said in a statement: "It's unfortunate that some Republicans are attempting to undermine the President's efforts to achieve peace in the Middle East and ensure Iran never has a nuclear weapon."

For his part, Vance has repeatedly insisted that Iran must fully meet its obligations under the U.S.-Iran memorandum of understanding if it wants any sanctions relief or other benefits under the emerging deal aimed at ending the conflict. He has stressed that any economic concessions are conditional on verified compliance with terms covering its nuclear program and regional security commitments, according to Reuters reporting and White House briefings.

"What we have said is that we're willing to talk about unfreezing assets, but a much, much bigger deal is unsanctioning their economy — so long as they make the long-term commitments on the nuclear program," Vance said.

"The deal is structured to ensure that the US and its allies' concerns are prioritized, and that if the Islamic Republic of Iran meets its obligations, then economic benefits will flow to them and to the entire region," Vance wrote on X.