US politicians are using profanity in public far more frequently than in the past, according to research published by Cardiff University politics lecturer Dr Joseph Phillips.

Some 87% of the 692 documented instances of presidents, vice presidents, and presidential candidates using profanity in public have occurred in just the last decade, Phillips wrote. The overwhelming majority of those cases – 78% – came from President Donald Trump and his predecessor Joe Biden, according to the study published this week.

On Wednesday, Trump was heard using another expletive following an Iranian attack on US forces in Jordan. According to Fox News’ chief foreign affairs correspondent, Trey Yingst, the president said: “We’re going to beat the f**king s**t out of them.” Biden previously made headlines while serving as vice president, when he was caught on a hot mic telling then-President Barack Obama that signing the 2010 Affordable Care Act was a “big f**king deal.”

For US presidents to use profanity publicly was once exceptionally rare, Phillips noted. According to the study, President Woodrow Wilson became the first to publicly use a naughty word, when he said he’d made a “conspicuous *ss of himself” in 1919.

However, Trump has introduced a broader range of profanities into presidential rhetoric, using words such as “bullsh*t,” “ba***rd,” “b***ch,” and “f**k” in speeches, interviews, and social media posts, according to Phillips.

The researcher argued that the trend reflects broader changes in political communication rather than simply the personalities of individual politicians. He said profanity has become increasingly common in US politics, with politicians at all levels of government swearing more frequently than in previous decades.

Phillips also argued that politicians increasingly use profanity because it can signal authenticity at a time when public trust in politics is low. Since swearing is common in everyday conversation, using it publicly may help politicians appear more relatable and less carefully scripted. He added that even voters who dislike political profanity are unlikely to change their political allegiances over it, given the deep ideological divisions between the two major parties.

BQ: “Profanity can be a signal of authenticity. In a time of low political trust, signals that a politician is ‘authentic’ are at a premium.”

The study comes as public attitudes toward swearing continue to shift. A series of YouGov polls published last year found that younger Americans were significantly more accepting of profanity at work, on social media, and in front of children than older respondents. Some 21% of adults aged 18-29 considered swearing in front of children completely or somewhat acceptable, compared with just 4% of those aged 65 and older.