Despite general support for war, several Republicans say boots on the ground would be a political Rubicon for US President Donald Trump.

United States Representative Nancy Mace, a Republican, has said Congress should have a say in any decisions to deploy troops to Iran, further underscoring division within US President Donald Trump’s political party.

Mace’s comments on Sunday came days after she emerged from a classified House of Representatives briefing on the war, saying it had raised concerns over the administration’s plans.

They also came on the same day the Washington Post reported the Pentagon is preparing for limited ground operations in Iran, including raids on Kharg Island and sites near the Strait of Hormuz.

“If we’re going to do a conventional ground operation with Marines and 82nd Airborne that is a ground war that I believe Congress should have a say and we should be briefed,” Mace said during an interview on CNN.

“We don’t want troops on the ground,” Mace added.

“I think that’s a line for a lot of people. If we’re going to do that, then come to Congress and get the proper authorities to do so.”

Trump has so far not publicly supported deploying US troops to Iran, but has maintained that all options remain on the table. He has broadly claimed success in the month since the US and Israel launched the war on February 28, but his endgame and final timeline for the conflict have remained unclear.

Military analysts and Trump’s own director of national intelligence have said that while Iran’s military capabilities have been diminished in the fighting, the country still maintains the ability to inflict damage on the region and to potentially rebuild.

Many experts have also pointed to the limits of using air power alone in fully degrading Iran’s military capabilities, destroying its nuclear programme, or in achieving more comprehensive regime change.

In a statement on Sunday, White House press secretary Karoline Leavitt did not deny the Washington Post’s report, but said the Pentagon regularly prepares a range of options for the president to review.

“It’s the job of the Pentagon to make preparations in order to give the commander-in-chief maximum optionality. It does not mean the president has made a decision,” Leavitt told the newspaper.

Inter-party divisions

Deploying boots on the ground has been a major political Rubicon for Trump, who has long favoured swift and finite military action abroad in what he calls an “America First” strategy.

The decision would also be a major gut check for Republican lawmakers, who have generally thrown their support behind Trump even as influential figures in his “Make America Great Again” (MAGA) movement have condemned the war.

That was largely on display at the Conservative Political Action Conference (CPAC) gathering held in Dallas, Texas over the weekend, where several speakers cheered the war or avoided the issue altogether.

However, former member of Congress and Trump ally Matt Gaetz directly decried any possible ground invasion.

“A ground invasion of Iran will make our country poorer and less safe,” he said. “It will mean higher gas prices, higher food prices, and I’m not sure we would end up killing more terrorists than we would create.”

The US has increased its military presence in the region in recent days, with the US Central Command (CENTCOM) saying about 3,500 additional soldiers arrived in the Middle East on board the USS Tripoli on Saturday.

About 2,000 soldiers from the US Army’s 82nd Airborne Division were diverted from the Asia Pacific region prior to that.

Last week, the Wall Street Journal reported that Trump was weighing sending an additional 10,000 troops to the region, where about 40,000 US troops are typically stationed.

Speaking to Politico last week, Representatives Eli Crane and Derrick Van Orden, both Republicans and former members of the military, also said their support for the war would shift if Trump deployed troops.

“My biggest concern this whole time is that this would turn into another long Middle Eastern war,” Crane told the news site.

“Though I don’t want to try and take away any of the president’s ability to carry out this operation, I know a lot of our supporters and a lot of members of Congress are very concerned,” he said.