Washington, DC – As United States President Donald Trump lauded what he called the “spectacular military success” of the strikes he authorised against Iran, Democrats were quick to accuse him of overstepping his authority.

Numerous critics accused Trump late on Saturday of violating the US Constitution by launching military attacks against Iran’s nuclear sites without the approval of Congress.

“Trump said he would end wars; now he has dragged America into one,” Senator Christopher Van Hollen Junior said in a statement.

“His actions are a clear violation of our Constitution – ignoring the requirement that only the Congress has the authority to declare war.”

In the lead up to the US attacks, legislators from both main parties have pushed measures to compel Trump to approach Congress before launching any strikes.

The US Constitution gives Congress the authority to declare war or authorise the use of force for specific purposes.

Trump’s “Make America Great Again” (MAGA) base has also been vehement in its opposition to the US joining Israel’s war. It has pointed out that Trump won the election on the promise not to commit Washington to yet another war in the Middle East. They want Trump to focus on domestic issues, particularly the economy.

‘Grounds for impeachment’

Lawmakers’ authority over the military was further enshrined in the War Powers Resolution of 1973, which curbed the president’s war-making powers.

Progressive Congresswoman Alexandria Ocasio-Cortez said Trump violated the constitution and the War Powers Resolution.

“He has impulsively risked launching a war that may ensnare us for generations. It is absolutely and clearly grounds for impeachment,” she said.

The president is the commander-in-chief of the armed forces, so he can order attacks, but his decisions must be within the guidelines of what is authorised by Congress.

However, the president can order the military in the case of a “sudden attack” or to respond to emergencies.

Several Democrats were quick to note that Iran’s nuclear facilities, which have been operating for years, did not pose an imminent threat to the US.

The US intelligence community confirmed in an assessment in March that Iran is not building a nuclear weapon.

Trump has increasingly relied on executive powers in governing domestically, and now he appears to be sidelining Congress in his foreign policy.

But with Republicans in control of the Senate and the House of Representatives, lawmakers have few tools to influence his military decision. Impeachment is almost out of the question.

President Trump sending U.S. troops to bomb Iran without the consent of Congress is a blatant violation of our Constitution. pic.twitter.com/pqzAeS4K19

— Congresswoman Rashida Tlaib (@RepRashida) June 22, 2025

No legal justification for strikes

Lawmakers have introduced bills under the War Powers Resolution to ban attacks on Iran without the approval of Congress, but Trump is likely to veto the proposals if they pass.

Congress could overturn the veto with two-thirds majorities in the House and the Senate, but Trump’s strikes have enough support to make that outcome unlikely.

The US president has not provided a legal justification for the strikes, but he is likely to argue that he was responding to an urgent situation or cite an existing military authorisation.

In the aftermath of the 9/11 attacks in 2001, Congress passed a law allowing then-President George W Bush to launch what would become the global “war on terror”.

Millions of people have been killed and societies devastated due to the US wars on Iraq, Afghanistan, Libya, among others, waged as part of the so-called “war on terror”. It has also cost trillions of dollars and the lives of thousands of US soldiers.

In 2002, lawmakers approved another authorisation to allow the invasion of Iraq a year later.

These laws, known as the Authorisation for Use of Military Force (AUMF), remain in place, and previous presidents have invoked them to justify attacks that were not specifically approved by Congress.

Brian Finucane, a senior adviser with the US programme of the International Crisis Group and former State Department lawyer, said the attack on Iran is “patently illegal”.

“Even under the prevailing executive branch doctrine, this is likely to constitute ‘war’ requiring congressional authorization,” he wrote in a social media post.

Statement from Rep. Ilhan Omar on U.S. Bombing of Iran:

“The strikes on Iran, ordered by President Trump and executed without congressional authorization, mark a dangerous and reckless escalation of an already volatile conflict in the Middle East.

“Military strikes will not…

— Rep. Ilhan Omar (@Ilhan) June 22, 2025

Key progressive Senator Bernie Sanders was speaking at a rally in Oklahoma when Trump announced the attack.

As Sanders told the crowd about the US strikes, attendees started chanting: “No more war!”

“It is so grossly unconstitutional,” he said. “All of you know that the only entity that can take this country to war is the US Congress; the president does not have that right.”

Former Democratic House Speaker Nancy Pelosi said lawmakers will be “demanding answers” from the administration.

“Tonight, the President ignored the Constitution by unilaterally engaging our military without Congressional authorization,” she said in a social media post.