As the U.S. military campaign against Iran threatens to complicate President Donald Trump’s legacy, two senior aides — Vice President JD Vance and Secretary of State Marco Rubio — are increasingly prominent in discussions about Republican leadership after Trump.
Seen by many as possible heirs to the president, Vance and Rubio have been drawn into delicate negotiations aimed at ending the conflict. Their differing approaches to the war and public profiles could shape their prospects ahead of the 2028 presidential race, when Trump will be term-limited.
Vance has been cautious and measured, reflecting his long-standing skepticism of extended U.S. military engagements. Rubio has taken a strongly hawkish line, aligning closely with Trump and emerging as one of the administration’s most vocal defenders of the campaign.
Trump has said both men are involved in efforts to pressure Iran to dismantle its nuclear and ballistic missile programs and ensure oil flows freely through the Strait of Hormuz. Privately, the president has asked aides and allies “JD or Marco?” when discussing the post-Trump future, according to people familiar with his comments.
Political strategists and Republican officials say the outcome of the operation, now in its fifth week, could influence which aide gains momentum. A quick, decisive result favorable to U.S. objectives could boost Rubio, who also serves as Trump’s national security adviser and could be portrayed as steady in crisis. A prolonged conflict might benefit Vance, allowing him to appeal to voters uneasy about extended wars while maintaining loyalty to Trump.
Trump’s standing has also been affected: a recent Reuters/Ipsos poll showed his approval at 36%, the lowest since he returned to the White House, hurt by rising fuel costs and public disapproval of the Iran campaign.
Some Republicans are watching which aide appears to win the president’s favor during the conflict. Several see signs Trump has warmed to Rubio, though they add he could shift his preference quickly. The White House dismissed suggestions Trump is signaling a choice. “No amount of crazed media speculation about Vice President Vance and Secretary Rubio will deter this administration’s mission of fighting for the American people,” spokesman Steven Cheung said.
From Rivals to Potential Successors
Vance, 41, a former Marine and Iraq veteran, has long cautioned against U.S. entanglements overseas. He has limited his public remarks on Iran and emphasized his skepticism about prolonged military commitments. Once a self-described “never-Trumper,” Vance wrote in the Wall Street Journal in 2023 that one of Trump’s foreign-policy strengths was avoiding new wars during his first term.
The White House has downplayed any rift. Standing with Trump in the Oval Office earlier this month, Vance said he supported Trump’s handling of the conflict and agreed Iran must be prevented from obtaining nuclear weapons. If envoys such as Steve Witkoff and Jared Kushner make progress, Vance could assume a more direct negotiating role, a person familiar with the situation said.
“Vice President Vance is proud to be a part of a highly effective team that, under President Trump’s bold leadership, has had incredible success in making America safer, more secure and more prosperous,” a Vance spokeswoman said.
A senior White House official said Trump tolerates ideological differences as long as aides remain loyal, and that Vance’s skepticism has helped inform the administration about where part of its base stands. A person familiar with Vance’s thinking said he plans to wait until after the November midterms before deciding whether to run in 2028.
Vance topped the Conservative Political Action Conference’s straw poll, receiving about 53% of votes from more than 1,600 attendees. Rubio finished second with 35%, up from 3% the prior year.
Rubio, 54, has said he would not run if Vance does and has indicated he’d be willing to be Vance’s running mate. But any perceived weakness by Vance could encourage Rubio and others to test the waters. Republican strategist Ron Bonjean warned that Trump’s memory is long and that a lack of overt allegiance to the president could cost an aide his endorsement — a key asset for candidates in today’s GOP.
Trump has suggested Vance and Rubio could run together, and a senior official said the president does not intend to anoint a successor.
Polling shows strong GOP favorability for both men. A Reuters/Ipsos survey found 79% of Republicans view Vance positively and 71% view Rubio positively; Trump’s favorable rating among Republicans was 79%.
Rubio’s Path and Fallout
Rubio, who clashed with Trump during the 2016 campaign, has since set aside past tensions and developed a close relationship with the president’s team, State Department spokesman Tommy Pigott said. Rubio briefly drew criticism from some conservative backers after suggesting Israel played a role in pushing the U.S. toward war, but in subsequent weeks Trump has praised his efforts.
Asked whether he worried a protracted war could harm his political future, a senior State Department official said Rubio “has not spent a second thinking about this.”
Differences in Tone
At a televised Cabinet meeting, the contrast between the two men was evident. Rubio delivered a robust defense of Trump’s strikes on Iran: “He’s not going to leave a danger like this in place,” he said. Vance sounded more measured, focusing on options to deprive Iran of a nuclear weapon and closing with well-wishes for Christians and U.S. troops during Holy Week and Easter: “We continue to stand behind you… and continue to support you every step of the way.”
Conservative figures say the campaign’s political consequences are substantial. “If it is seen as successful at getting the job done… I think people will be politically rewarded for doing the right thing,” CPAC leader Matt Schlapp said. “If it goes on and on and on… I think the politics are tough.”
Republicans broadly approve of the strikes, with Reuters/Ipsos polling showing 75% support among GOP respondents, compared with 6% of Democrats and 24% of independents. As the conflict unfolds, party leaders and voters alike are watching which of Trump’s lieutenants emerges strongest — and how that will shape the GOP’s path after Trump.
