JD Vance, now the lone dove in Donald Trump's cabinet after Tulsi Gabbard's resignation, has been left more isolated than ever and is even considering abandoning a run for the presidency in 2028, multiple sources tell the Daily Mail.

Gabbard's resignation letter cited her husband's diagnosis with a rare form of cancer.

But the whispers racing through the West Wing find common ground: Iran.

Vance's most senior non-interventionist ally is gone, and even as he expressed his sorrow for the exit of his 'dear friend' on Friday, insiders told the Daily Mail that his own future is at the front of his mind, while his rivals sharpen their blades.

'Vance is a non-event in the West Wing,' a source close to the President told Daily Mail.

Vance's isolation comes at a moment when Marco Rubio's stock inside the West Wing has never been higher, with the Secretary of State helping to plan an invasion of Cuba, while the Vice President flails in peace negotiations with Iran.

The Vice President's dovish brand of foreign policy has set him on a collision course with Trump, the sources say, the rift deepening as Trump embraces his wartime-leader image. 

'The President has made it very clear in recent months that he doesn't abide by this strong, silent Gary Cooper style approach to foreign policy,' a White House insider told the Daily Mail.

'He's loud, he's active. These guys prefer to speak softly and carry a big stick, but Trump speaks loudly and carries a massive cannon,' the source added.

Vance privately urged Trump against authorizing full-scale strikes on Iran in February. 

He encouraged the president to authorize a limited, punitive strike instead of a full-scale operation, and warned him that a wider war could trigger regional chaos and heavy casualties, according to the New York Times.

Trump himself has since acknowledged the divide, conceding that his Vice President was 'maybe less enthusiastic' at the start of the war and 'philosophically a little bit different' on the decision to strike.

Gabbard, who like Vance, was viewed as a brake on Trump's hawkish instincts, never quite fit the new mold either.

'I don't think she was as opposed as a lot of people think she was. She recognized that her job was to serve the President,' the same insider said.

But Vance, unlike Gabbard, has no graceful exit on offer.

As Vance's non-interventionist influence faded, Rubio's expanded, with the Secretary of State emerging as the dominant foreign policy voice in Trump's orbit.

'Rubio has more mojo than Vance. The President listens to him. Vance is out of step and has been for a long time,' the White House insider said.

The source cautioned that Rubio's dominance may prove fleeting. By championing an unpopular war effort, the Secretary of State risks burning through political capital in real time and alienating both Trump's base and the wider American public.

Rumors are also circulating in the West Wing that Vance is weighing whether to step back from the 2028 race entirely as a tactical move, according to the source.

The insider noted it may be better for him not to 'own everything that's gone on in the last couple of years.'

The Vice President is just 41, and allies have floated political alternatives that would let him sit out the next cycle and re-emerge later.

But a separate source close to the Vice President told Daily Mail that sitting on the sidelines would be folly.

'Anyone who wants to be a viable nominee for president has a very small window. And if you don't go when that window is open, most likely it never opens up again,' the source close to Vance said.

Time can be unforgiving.

A 2032 run would pit Vance against a sitting incumbent, and only Jimmy Carter, George HW Bush, and Donald Trump have lost a re-election in the last half-century.

A 2032 or 2036 bid for the presidency would require Vance to remain politically relevant for a full decade out of elected office.

The source said this task would be 'extremely hard when you're out of the limelight.'

'Age-wise he'd be young enough. But momentum-wise, there'd be a shinier penny on the street.'

Vance's only viable path to a future in the White House runs straight through 2028, according to the source.

Gabbard's resignation follows the March departure of Joe Kent, another key Vance ally inside the administration, who stepped down in protest over the Iran war.

Kent submitted his resignation to Vance alongside Gabbard's the day before it went public.

The Vice President reportedly urged Kent not to disparage the President or the administration on his way out. Kent disregarded the advice, later accusing Israel of misleading the President into the war with Iran.

Kent's departure was an early warning sign that the Vice President's faction was being pushed out of Trump's national security orbit.

Gabbard's exit now leaves Vance without his two most visible internal allies opposing the war.

Vance, in his statement, credited Gabbard as a 'great asset to the administration' and pointedly mourned the loss of his departed 'loyal confidante.' 

The Daily Mail has contacted Vance's office for comment.