NextFin News - Marco Rubio now sits at the center of American foreign policy in a configuration Washington has not seen in half a century: as Secretary of State and acting National Security Adviser at the same time, the first person to hold both jobs since Henry Kissinger in the 1970s. The arrangement, which began as an interim fix after Mike Waltz's May 2025 ouster, has hardened into the defining structure of Donald Trump's second-term foreign policy - and it is drawing fresh scrutiny as Rubio steers the administration through simultaneous crises in Iran, Ukraine, Gaza, and Venezuela.
The Consolidation of Power
On May 1, 2025, President Trump announced he was removing Mike Waltz as national security adviser and nominating him to be U.S. ambassador to the United Nations. The trigger was a Signal group chat in which Waltz had inadvertently added journalist Jeffrey Goldberg while top national security officials discussed sensitive military plans, including a U.S. strike in Yemen. Waltz's deputy, Alex Wong, an Asia specialist who had served on North Korea policy during Trump's first term, was also forced out.
"In the interim, Secretary of State Marco Rubio will serve as National Security Advisor, while continuing his strong leadership at the State Department," Trump wrote on social media that day.At a White House event hours earlier, the president had offered a simpler endorsement:
"When I have a problem, I call up Marco. He gets it solved."
More than 16 months later, the interim arrangement shows no sign of ending. Rubio was confirmed by the Senate in a 99-0 vote on January 20, 2025, and sworn in as the 72nd Secretary of State on January 21, 2025 - the first cabinet member confirmed in Trump's second term and the first Latino to hold either the secretary of state post or the acting national security adviser role, making him the highest-ranking Hispanic American official in U.S. history. He also briefly held two more portfolios: acting administrator of the U.S. Agency for International Development until August 2025, and acting archivist of the United States from February 2025 to February 2026.
The precedent is thin. Henry Kissinger held both the secretary of state and national security adviser posts from 1973 to 1975 under Richard Nixon and Gerald Ford - a period remembered for shuttle diplomacy in the Middle East and the opening to China. Rubio's tenure has been no less consequential. A 2026 TIME profile placed him on its list of the world's 100 most influential people, describing the dual role as "a power monopoly held only once before, by Henry Kissinger" and putting Rubio "at the center of some of the biggest moves of Trump's second term, including the capture of Venezuela's leader, the massive joint military assault on Iran, and the ongoing machinations around the pursuit of peace in Ukraine and the Middle East."
The Machinery Behind the Man
The consolidation is not just about one man holding two titles. It is about the deliberate dismantling of the machinery that used to stand between a president and his foreign policy.
Within weeks of Rubio's appointment, the National Security Council was cut by roughly half. Andy Baker, national security adviser to Vice President JD Vance, and Robert Gabriel, a White House deputy chief of staff, were named deputy national security advisers. Gabriel served from May 23, 2025, to May 20, 2026, and was succeeded by Michael Needham. Reporting in 2026 described Trump and Rubio as having "orchestrated a vast restructuring of the National Security Council, reducing its size and transferring many of its powers to the State and Defense departments" - an effort aimed, in the White House's view, at an NSC filled with career officials who did not share the president's vision.
At the State Department, Rubio presided over an equally radical reorganization: the dismantling of USAID as an independent agency and its absorption into State, plans to cut U.S. government jobs by 15%, and the closure or consolidation of more than 100 bureaus worldwide. He also oversaw a sweeping cull of the visa system, revoking hundreds, if not thousands, of student visas, and negotiated agreements to send immigrants accused of crimes to third countries - most notably El Salvador - in arrangements now being challenged in federal court.
The legal architecture came early. Executive Order 14394, "One Voice for America's Foreign Relations," signed February 12, 2025, mandated that all officers and employees responsible for implementing U.S. foreign policy act within the direction of the president or face professional discipline, including separation. It gave the secretary of state "sole and exclusive discretion" to report conduct warranting discipline. The order effectively made Rubio the president's enforcer across the foreign policy bureaucracy.
In a December 2025 press conference, Rubio framed the shift plainly.
"Today I am the Secretary of State for Donald J. Trump, the President of the United States, and my job is to implement the President's foreign policy, provide advice, provide counsel, provide ideas," he said. "But in the end, our job is to implement that."
Why It Is Different This Time
The question critics keep returning to is not whether Rubio can hold two jobs. It is whether anyone can - and whether the answer matters less than the point of the exercise.
John Bolton, Trump's national security adviser in the first term, put it bluntly:
"I'm not sure anybody, including Henry Kissinger, really has the bandwidth to do it."Thomas Wright, an NSC official in the Biden administration and now a senior fellow at the Brookings Institution, said the national security adviser post alone is "more than a full-time job," recalling that Jake Sullivan and his deputy worked 14 to 15 hours a day, six to seven days a week.
"It is just very hard to comprehend the idea that you can do this job sort of part time," Wright said.
But that framing may miss the design. The Kissinger comparison describes the concentration of titles; it does not describe the concentration of process. Kissinger inherited an interagency system and bent it to his will. Rubio inherited a system that had already been hollowed out - and then removed more of it.
The structural change is the story. The National Security Council was created in 1947 to be an honest broker: it exists to surface competing views, force agencies to argue their cases, and present the president with options rather than conclusions. With the NSC staff halved and its coordinating powers shifted to State and Defense - agencies Rubio now directly controls - the broker function has effectively been internalized within a single office. There is no longer a neutral referee between diplomacy and defense; there is one man who runs both, reporting to a president who has said he alone decides.
"This is a top-down, not a bottom-up process," a White House official said. "The president was elected by the American people to carry out his foreign policy agenda, and he ultimately decides, based on what he feels, is the best choice for the American people."
Alexander Gray, who served as chief of staff for the NSC in Trump's first term and is now a senior fellow at the Atlantic Council, offered the administration's best-case reading:
"The benefit, so to speak, of a national security adviser who's also secretary of state in terms of shaping the process is less significant when people are generally aligned."In other words, the honest broker matters only when there is genuine disagreement to broker.
The Second-Order Problem
The immediate risk of the dual role is overload - one man, two full-time jobs, and a world that does not wait. The second-order risk is subtler and more consequential: when the same person controls both the diplomatic instrument and the process that coordinates military and intelligence options, the system loses its internal friction.
Friction in foreign policy is usually a bug. But it is also a safety mechanism. The NSC's interagency process forces a war plan to survive scrutiny from diplomats who will have to clean up afterward, and forces a diplomatic initiative to survive scrutiny from soldiers who will have to enforce it. Remove that friction, and decisions travel faster - which is precisely the point of the redesign. But speed without dissent is how administrations inherit consequences they did not fully foresee.
The warning signs are already visible. On September 17, 2026, eight Democratic senators - Jeanne Shaheen, Richard Blumenthal, Tammy Duckworth, Mazie Hirono, Tim Kaine, Mark Kelly, Angus King, and Jacky Rosen - sent Rubio a letter about the Pentagon's ongoing Europe Force Posture Review.
"In your capacity as National Security Advisor and Secretary of State, we write with urgency to request that the Department of Defense's ongoing Europe Force Posture Review is conducted in close consultation and meaningful partnership with the Department of State," they wrote.The senators added:
"It is precisely because you hold both roles that we are concerned by reports that the Department of Defense is not adequately consulting with the Department of State on this review."
The letter reported that U.S. ambassadors and chiefs of mission in affected European countries had been excluded from consultations, that State had not been adequately included in bilateral discussions with allies, and that it was unclear whether State had been consulted on a questionnaire sent to allies in late July. The questionnaire asked whether each country "has been publicly supportive of U.S. foreign policy priorities" - a question the senators called "squarely within the State Department's domain."
Here is the paradox: Rubio holds both roles precisely so that diplomacy and defense are aligned. Yet the senators' complaint is that, in practice, the defense side is running ahead of the diplomatic side - and the one person who could force them into the same room is the same person both sides report to. The conflict is not a conflict of interest; it is a conflict of bandwidth.
Emily Horne, who served as an NSC spokesperson in the Biden administration and now writes the Spin Class newsletter, questioned how much advanced analysis was conducted on the geopolitical implications of the Venezuela operation that led to Maduro's capture on January 3, 2026.
"However, that's a different thing than saying that we were bringing everything we could to both executing this operation and ensuring that we know what the day after or the week after and beyond look like," Horne said.The White House pushed back, with an official calling such concerns "inside baseball" and saying the criticism was "totally negated by the fact that things are stable and going well and there is a cooperative economic relationship in place, and we have maximum leverage over the regime."
The Cyclical Question: Will This Last?
Is the dual role a structural shift or a cyclical convenience? The evidence points to structure - but with a built-in expiration date tied to one man.
The structural case is strong. The NSC cuts, the USAID dismantling, the 15% staffing reduction, the closure of more than 100 bureaus, and Executive Order 14394 are not temporary measures. They are institutional changes that will outlast any single personnel arrangement. Even if a future president separates the two roles, the machinery Rubio built - a smaller NSC, a State Department that absorbs development assistance, a legal framework that makes the secretary of state the president's sole enforcer - will remain.
But the personal concentration is almost certainly cyclical. No institution tolerates a permanent merger of secretary of state and national security adviser; the workload is unsustainable, and the accountability it creates is dangerous for any president whose fortunes turn. Kissinger held both posts for only two years. Rubio's tenure in the dual role will end when Trump decides it has outlived its usefulness, when a crisis exposes its limits, or when Rubio himself chooses to leave - speculation about a 2028 presidential run or a private-sector future is already circulating among people close to him.
The TIME profile captured the wager:
"The nimble shift from Trump critic to the executor of Trump's foreign policy has repaired Rubio's relationship with the MAGA base and puts him in position to possibly inherit the Trumpist movement in 2028. Yet it also comes with risks: he owns the Trump record now in a way that could one day prove problematic. Betting on Trump's instincts is as high risk as it might be high reward."
In 2016, Rubio was a Trump rival the president mocked as "Little Marco." Eight years later, he is the executor of Trump's foreign policy - and he has largely abandoned his old advocacy for foreign aid and democracy promotion overseas. His doctrine, as he laid it out in December 2025, is that foreign policy must make America "safer or stronger or more prosperous - hopefully all three, but at least one of those three." It is a transactional doctrine, and it fits the administration that gave him power.
What to Watch
Three signals will determine whether this structure endures or cracks.
First, the Iran and Ukraine files. Rubio has taken a behind-the-scenes role on the Iran war, keeping distance that could be politically advantageous. If either conflict deteriorates - if the Iran ceasefire collapses or if Ukraine talks stall - the dual-role structure will face its first real stress test, and the question of bandwidth will move from theoretical to operational.
Second, the Europe Force Posture Review. If the Pentagon proceeds with force reductions that alienate NATO allies without State Department input, and Rubio is forced to defend decisions he did not adequately shape, the senators' warning will have been vindicated - and the case for separating the roles will harden.
Third, the 2026 midterm elections. Rubio's political future is bound to Trump's record. If Republicans lose ground, the executor of foreign policy becomes a natural target; if they hold, Rubio's position strengthens. Either way, the dual role is a 2028 question as much as a 2026 one.
The falsifying signal is specific: if a major foreign policy failure can be traced directly to the absence of interagency review - a military decision made without diplomatic input, or a diplomatic commitment made without military review - and the administration acknowledges the process gap, the argument that the dual role improves decision-making collapses. Until then, the White House's defense is simple: it works, because the president decides, and Rubio delivers.
The Bottom Line
Rubio's expansive role is not an accident of personnel. It is the institutional expression of a presidency that has no use for process that slows it down. The dual title concentrates authority in one man; the hollowed-out NSC removes the referee; the executive order removes the dissenters. What remains is a foreign policy made at the top and executed without friction - fast, coherent, and exposed to the one risk no redesign can eliminate: the risk that the man at the center gets something wrong, and no one is left whose job it is to tell him.
This is not the Kissinger model. Kissinger bent the system; Rubio replaced it. The question is not whether one man can do two jobs. It is whether a superpower can afford a foreign policy with no brakes.
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