US President Donald Trump speaks in a way unlike any of his predecessors. His distinctive and highly recognisable style may even play a role in his appeal to his political base. Since the infamous Access Hollywood tapes, he has got away with saying things none of his predecessors would have ever dreamed of saying in public. This is particularly striking in a country that was shocked to learn in the 1970s that Richard Nixon used dirty words in the Oval Office.

Scholars have described Trump’s rhetorical style as “unbalanced vituperation”, stressing his constant use of demeaning language, false equivalences and exclusion.

Even more strikingly, a recent study found Trump’s use of violent vocabulary, especially language linked to war and crime, represents a radical departure from US political tradition.

Since the beginning of the war with Iran, Trump’s rhetoric has become even more combative and outrageous, marking an even sharper shift from the language used by his predecessors in similar occasions.

What effect does this have and what does it tell us about the commander-in-chief’s state of mind?

Demeaning opponents

Trump announced the death of Iran’s Supreme Leader Ayatollah Ali Khamenei by calling him a “wretched and vile man”. Later, in a Truth Social post, he called him “one of the most evil people in history” and referred to “his gang of bloodthirsty thugs”.

A few days later, he continued denigrating leaders of the Iranian regime, describing them as “deranged scumbags” whose killing was for him a “great honor”. He has also insulted Mojtaba Khamenei, who succeeded his father as Iran’s Supreme Leader, describing him as “unacceptable” and a “lightweight”. He also stated during an interview that he believes Mojtaba is alive but “damaged”.

Americans are no strangers to their presidents using strong language to describe adversaries. Ronald Reagan famously referred to the Soviet Union as an “evil empire”, and George W. Bush warned of an “Axis of Evil”.

Yet such rhetoric rarely extended to personal insults against individual foreign leaders. Leaders generally bring a mood to these speeches that recognises their words will be frightening for many people. It also acknowledges that in a war situation, lives will inevitably be lost.

George W. Bush, for example, simply stated that US forces “captured Saddam Hussein alive”. Barack Obama announced to the nation Osama bin Laden’s killing by addressing the mastermind of the worst terrorist attack on US soil simply as “Osama bin Laden, leader of al Qaeda, and a terrorist”.

Trump has also shown little restraint in issuing threats. At the beginning of the conflict he stated in an interview that they had not even started hitting Iran hard and that the “big wave” was coming soon. He later posted on Truth Social that he was ready to hit Iran “twenty times harder” and threatened to “make it virtually impossible for Iran to ever be built back, as a Nation, again”, adding that “death, fire and fury will reign [sic] upon them”. At one point, he even suggested that he might strike Iran’s Kharg Island oil export hub again “just for fun”.

This language is not only vitriolic. It also is in sharp contrast with the rhetoric of past US presidents who often emphasised restraint in the use of force and showed willingness to de-escalate military conflicts.

Previous presidents have been very clear about the strength of the US military, but they have also tried to focus on diplomacy and negotiation.

Obama, talking about Syria, famously remarked that “the United States military doesn’t do pinpricks”. Yet, moments later, he asked Congress to postpone a vote authorising the use of force while his administration pursued diplomatic options.

Nixon stated during the Vietnam war that “The peace we seek to win is not victory over any other people, but the peace that comes ‘with healing in its wings’; with compassion for those who have suffered; with understanding for those who have opposed us; with the opportunity for all the peoples of this Earth to choose their own destiny”.

Trump’s threats of escalation also raise concerns about the safety of civilians and the protection of critical infrastructure. He recently stated he “didn’t do anything to do with the energy lines, because having to rebuild that would take years”. This remark suggests some awareness of the consequences of such actions.

Even so, earlier presidents often distinguished explicitly between military targets and civilian populations. George H. W. Bush, during the Gulf War, declared “our quarrel is not with the people of Iraq. We do not wish for them to suffer”.

In 2003, George W. Bush warned Iraqi military and civilian personnel: “do not destroy oils wells, a source of wealth that belongs to the Iraqi people. Do not obey any command to use weapons of mass destruction against anyone, including the Iraqi people”.

Words matter

It is still unclear why Trump’s rhetoric is so violent and so far removed from the language of virtually every US president before him. A 2020 study found Trump’s foreign policy rhetoric often aims to create a sense of crisis to mobilise his domestic base – or distract from political troubles at home.

Some observers argue Trump has used, or even manufactured, national crises as a mechanism to expand executive power through emergency declarations. Whether this is the case in the current war with Iran remains to be seen.

But words certainly matter.

On December 19 1945, US President Harry S. Truman issued a special message to Congress recommending the Department of War and the Department of the Navy be merged into a single “Department of National Defense”. Between 1947 and 1949, Congress and the executive branch implemented this proposal. Many other countries went through a similar process in the postwar period, replacing the language of “war” from the name of their departments and ministries with the more restrained term “defence”.

Seventy-six years later, in 2025, Trump reversed that tradition with an executive order renaming the Department of Defense as the US Department of War.

This same executive order clearly states that the new name demonstrates a willingness to fight wars at a moment’s notice. And the reason is not only to defend, but to “secure what is ours”.

Viewed in light of the current war with Iran, those words provide some insight into the administration’s thinking. They also invite reflection on other words coming out of the administration and its supporters, including the “Gulf of America”, the idea of Canada as the “51st state”, and even the far-fetched “Trump 2028” chant.