"This is Israel's war. This is not the United States' war."

The video was posted to YouTube less than two days after the US and Israel began their most recent attacks on Iran. It's been viewed more than 2 million times. But it wasn't made by an anti-Trump activist or critic of the president.

The monologue came from one of the most influential voices on the right of American politics: former Fox News host, Tucker Carlson.

"Countries become less free during war, a spirit of violence descends and people change fast," said Carlson, a long-time supporter of Donald Trump who reportedly met with the president several times last month in an attempt to dissuade him from ordering military action. "You can feel on people the bloodlust, the hate, and it accelerates."

Carlson's advice was clear: "Get out right away. It's just that simple. Of course, it's also incredibly complicated, but the first step is deciding that we're leaving."

This debate is the clearest indication yet of splits in the coalition - an "island of misfit toys" as one Republican operative dubbed it – that brought Trump back to the White House.

Arguments over the president's "America First" agenda - and who best supports it - have been raging for months.

But it is the war in Iran that has crystalised infighting which, some insiders worry, could hurt Republicans in November's midterm elections.

What polls indicate

It's common for US presidents to get a boost in popularity in the early stages of military action, as patriotism surges and people "rally round the flag".

Several polls conducted since the bombing indicate that a majority of Americans disapprove of the military action. In an NBC News survey, for instance, 54% disagree with how the president has handled Iran.

That divide breaks down along party lines, with 89% of Democrats opposed and 77% of Republicans in favour.

But look closer, and there are splits apparent on the right.

According to NBC, nine out of 10 Republicans that self-identify as "Maga" support the war.

These are Trump's ride-or-die supporters, the type of people who show up to his rallies wearing red hats and almost always support his agenda.

The same poll indicated that Republicans who don't call themselves Maga are much more sceptical about the war – just over half said they approved, and more than a third say they oppose it.

"The generation that the grassroots is composed of are a lot of people who went to Iraq, went to Afghanistan," says Vish Burra, a Republican activist from New York City who worked for disgraced former congressman George Santos and Maga-world media outlets.

"Once they did their tour in this kind of fruitless war effort… they come back, they see their towns hollowed out and the factories are gone and opioids have taken over."

Opposition to the war is likely to intensify if Trump sends troops on the ground, another poll found.

A Quinnipiac poll, conducted last weekend, found that while 85% of Republicans support military action in Iran, 52% of the party's supporters would oppose sending ground troops.

Some insiders think Trump may be able to navigate the political danger. Matt Wylie, a Republican consultant based in South Carolina, says that despite the splits, military action could bolster Trump's support among traditional Republicans - a category that overlaps both the Maga and non-Maga wings of the party.

"They still view America as a beacon of hope for freedom seeking people around the world - and that role carries responsibility: to defend our allies, protect free nations, and stand firm when tyranny threatens peace," he says.

But the contingent that disagrees with the president has some powerful voices, including Carlson, podcaster Joe Rogan - who called the Iran war "so insane" - and Marjorie Taylor Greene, the former Congresswoman from Georgia.

Greene broke with Trump last year in a furious spat that ended with her resignation.

"We voted for no more foreign wars, no more regime change," Greene wrote on X last weekend, one of a flurry of anti-war posts she has been cranking out. "Trump has betrayed his campaign promises of no more foreign wars."

Greene and Carlson have a few allies in public office, such as Republican Congressman Thomas Massie of Kentucky, who supported a failed measure last week which would have given Congress a veto on the war.

But they wield more sway online, among voters who regard themselves as "real Maga": politically disaffected people drawn to Trump by the ideas he promoted on the campaign trail, but who are now lukewarm about the man himself.

One influencer who proudly put a drawing of herself in a red hat on her X profile put their views succinctly: "I dont [sic] remember voting to 'Free Iran'. I voted to Make America Great Again."

Campaign promises

On X and other social platforms, posts have highlighted past anti-war statements made by Trump and his advisers.

"You're not going to have a war with me and you're not going to have a third world war with me," Trump told a crowd in New York City, just days before the 2024 election.

And last October Vice-President JD Vance recounted a conversation with conservative activist Charlie Kirk, prior to Kirk's assassination.

The vice-president credited Kirk as one of the reasons why Trump "never got the United States into a protracted military conflict, and never lost a single American in a Middle Eastern conflict".

Whether the conflict is "protracted" remains to be seen. But it is the most significant military operation under Trump to date. At least 13 Americans have been killed so far, including six killed in a plane crash in Iraq on Thursday. There have been casualties across Israel and Gulf countries. Hundreds of people have been killed in Lebanon as Israel exchanges fire with Hezbollah, and Iran has reported that more than 1,300 people have been killed.

Vish Burra, the Republican activist, contrasts what he calls "grassroots Maga", which he describes as non-interventionist, with the Republican donor class, which he paints as pro-war and pro-Israel.

But his own story points to a deeper rift on the American right, where anti-Israel sentiment has in some cases tipped over into antisemitism.

Burra was sacked from the right-wing One America News network for posting an AI-generated video showing cockroaches in a room with a Star of David on the door. He has said he did not mean to be antisemitic.

Others who share his views on Iran care less about appearing racist or antisemitic – including Nick Fuentes, a 27-year-old livestreamer.

Online, he sarcastically opines on current events and makes comments like: "Jews are running society, women need to shut the [expletive] up, blacks need to be imprisoned for the most part, and we would live in paradise."

Power vacuum

For years Fuentes, who did not respond to our interview requests, sniped at the Republican establishment from the sidelines.

But the assassination of Charlie Kirk - a towering figure on the US right - and wider discontent about issues including the economy and the Epstein files created a power vacuum.

Carlson invited Fuentes to his studio last October for a mostly friendly chat in which Fuentes toned down his more extreme views. It kicked off a huge debate on the right over the limits of their movement.

Now the extremists are trying to capitalise on much wider opposition to an unpopular war.

They make up just one tiny slice of opposition and are very loud online, but numerically small in comparison to voters of both parties and independents who oppose the war for various reasons.

But in the background, there is evidence to indicate that extreme views are spreading.

Rod Dreher, a conservative writer and friend of Vice-President Vance, says that during a recent trip to the US capital he took an informal poll of young men working in politics and asked them how much of their cohort could be classed as groypers - a term used for Fuentes's followers.

"The number I kept getting was 30 to 40%," he said. "And this really shocked me."

Vance has publicly criticised the extremists, at one point using a scatological insult against Fuentes during an interview with website Unherd. But Dreher says he's dismayed that Vance hasn't been more forceful in his denunciations.

"These people cannot be given a space within the broader mainstream conservative movement," Dreher told the BBC.

Everything depends on how long it lasts

Trump still remains, unsurprisingly, the most powerful force in the Republican Party, and his endorsement is being coveted by Republicans hoping to win Congressional midterm primaries which have already started in some states.

During previous bombing campaigns, stretching back to Trump's first term, online opposition on the right quieted after the fighting stopped.

David Azerrad, a political science professor at conservative Hillsdale College, said that "for now, I think the president can continue to ignore the nattering nabobs".

But the president is in the midst of a complicated and potentially protracted foreign conflict, and experts agree that everything depends on how long the war lasts and the effects it has on the US economy, particularly oil prices.

Support could ebb, says political strategist Matt Wiley, "especially if this drags on for months, if Trump puts troops on the ground, if more American lives are lost".