Washington, DC – The 60-day mark of the United States and Israel’s war with Iran represents a fork in the road for US lawmakers: will they assert their authority – either in support or against – the conflict, or remain silent?

It is a question that, experts say, lawmakers technically should not have to answer.

The US Constitution limits a president’s war-making powers. A subsequent law passed in 1973 – dubbed the War Powers Act – further codified that presidents must cease military action after 60 days, or receive congressional authorisation to legally continue.

But US presidents have for decades pushed the limits of their war-making authority, at times flouting the 60-day deadline, according to David Janovsky, acting director of the Constitution Project at the Project on Government Oversight (POGO). When that has happened, Congress has regularly shrugged.

Given the federal courts’ historical reluctance to weigh in on matters of armed conflict, it remains unclear what the pending deadline will bring.

That threshold will be reached on May 1, which marks 60 days from when US President Donald Trump officially “notified” Congress of the US-Israel attacks on Iran, which began on February 28.

“I think ultimately the question is, does Congress want a say in what’s happening?” Janovsky told Al Jazeera. “Either to say you have to stop right now, or to take some ownership and exercise some oversight?”

“The question for members is, are you going to own this or not?”

Will Congress act?

So far, political brass in Congress has not revealed how they plan to proceed in the days ahead.

Republicans, who control a slim majority in the Senate and the House of Representatives, have already scuttled a series of resolutions to rein in Trump’s military authorities. They have shown general unity in not publicly opposing the war with Iran, despite a handful of defectors siding with the majority of Democrats in opposition.

But Senate majority leader John Thune, the top Republican in the chamber, and Senator James Risch, the chairman of the influential Armed Services Committee, have so far not indicated any plans to bring forward legislation to authorise the war.

A vote on such legislation would be the first time lawmakers would be confronted with having to endorse the conflict on the record.

Regardless of whether or not Congress acts, the 60-day mark will be inflection point, after which, many constitutional experts argue, the war will enter a blatantly illegal phase under the War Powers Act.

Under the law, Trump could request a 30-day extension to complete a troop withdrawal, but that would preclude any new offensive operations.

According to the War Powers Act, the onus should be on Trump to stop the war after the deadline, regardless of what actions Congress takes, Janovsky explained. If not, his power to wage war would be subject to legal challenges in federal court.

But if the courts punt on the issue, and Congress does not act, the war could persist indefinitely on a murky legal footing.

“The courts historically have really, really tried to stay out of this kind of question,” Janovsky said, “which means it’s ultimately, more likely than not, going to be for the political branches to sort out.”

Republican divisions as deadline nears

Republicans have sent divided messages on how they view the 60-day deadline.

At least two Republicans, Senators Thom Tillis and Susan Collins, have suggested they would not vote to approve further US military action following May 1.

Senator Lisa Murkowski, a Republican, has said she is working on an authorisation of use of military force (AUMF) on the war, which would allow the US military to continue operations without a full declaration of war.

Such authorisations have been used in nearly all modern US wars, with Congress not officially declaring war since World War II.

Murkowski has suggested that some party members may not approve the Trump administration’s massive funding requests for the military campaign unless an AUMF is passed.

A handful of other Republican senators, including John Curtis and Jerry Moran, have publicly expressed unease at what they describe as a lack of information from the Trump administration, even though they have not called for a vote to authorise the war.

The debate comes as many Republican lawmakers, at least privately, are acknowledging that the military campaign is exacting potentially irreparable political damage in the run-up to the midterm elections in November, according to Andrew Day, a senior editor at the American Conservative.

The war and its knock-on economic implications have alienated parts of the coalition Trump relied on for his 2024 presidential election victory. Polls have shown dismal support among independents and slumping, if still majority, support among Republicans.

It has stirred a host of influential opponents within Trump’s Make America Great Again (MAGA) movement and conservatives writ large.

“Certainly [Republicans] are worried behind the scenes about the war with Iran,” Day said. “They recognise that it’s a political disaster.”

Does not necessarily translate

Still, awareness of the political toll will not necessarily result in official action in Congress.

With many weighing the political implications of publicly opposing Trump against the fallout of their inaction on the war, they are more likely to seek to influence the administration away from the spotlight, Day assessed.

“I’ve talked to congressional staffers who say that their bosses are privately critical of the war with Iran, but just don’t want that fight. They don’t want to alienate their donors, and they don’t want to draw the ire of Donald Trump, who is a force of nature when he’s angry,” Day said.

Concurrently, he said, the pause in fighting that began on April 8 offers Republicans a degree of political cover. That comes even as the US military has continued to blockade the Strait of Hormuz.

Trump, meanwhile, has repeatedly lodged threats of new attacks. Last week, Trump again threatened to “blow up the whole country”, hours before announcing the pause in fighting had been extended indefinitely. A new round of ceasefire talks has since stalled.

Henry Olsen, a senior fellow with the Ethics and Public Policy Center in Washington, DC, agreed that the vast majority of Republican lawmakers will take pains to avoid a definitive vote on the war in the current political landscape.

That is particularly true in the US House of Representatives, which is considered most at risk of a Democratic takeover in November.

“They’ll want to avoid this vote by whatever means possible,” he told Al Jazeera.

“[The 60-day mark] is a moment that they will try and ignore what is happening and try and make pass in the most unobtrusive way possible,” he told Al Jazeera.

An escalation?

Presidents have long tinkered with the definition of “hostilities” under the War Powers Act to avoid congressional approval.

US President Bill Clinton oversaw a host of limited military operations, including in Iraq and Somalia, that did not have congressional approval.

His deployment of US troops to the former Yugoslavia amid the Serbian ethnic cleansing of Kosovar Albanians in March 1999 stretched on for 79 days without authorisation and was subject to an unsuccessful legal challenge from lawmakers.

More recently, the administration of US President Barack Obama argued that the scope of military operations in Libya in 2011, which stretched beyond the 60-day deadline, was not subject to the War Powers Act.

State Department lawyers argued at the time that “US operations do not involve sustained fighting or active exchanges of fire with hostile forces, nor do they involve US ground troops”.

Still, POGO’s Janovsky said another round of Congressional inaction would represent a leap in even the most generous interpretations of what is and is not subject to the law.

To date, at least 3,300 people have been killed in Iran amid the US-Israel attacks. Dozens more, including 13 US military personnel, have been killed by Iran’s retaliatory strikes across the region.

The Trump administration has promised to decimate Iran’s military capabilities, hitting at least 13,000 targets before the pause in fighting began, while pledging to dismantle the country’s nuclear programme and foment wider regime change.

And while the administration has downplayed the issue amid the pause in fighting, it has not ruled out some form of future ground operation.

“One of the reasons we have gotten to this place is that for decades, Congress and the country have kind of shrugged their shoulders when presidents have pushed the boundaries of military intervention,” Janovsky said.

“This is hard to write off as any sort of limited military action,” he said. “This is a war.”