In what may be the only presidential debate before November’s election, Donald Trump and Kamala Harris squared off in Philadelphia on September 10. Topics discussed ranged from the economy to border security, abortion rights to the bizarre but debunked claims about Haitian immigrants consuming cats and dogs, the Taliban, and Ukraine. Since then, many polls and pundits have declared Harris the “winner” of the debate.

What does that actually mean, though? The US presidential debates are one of the major four-yearly “shows,” like the World Cup soccer, the UEFA Euro Cup, and the Olympics, in my opinion. The public continues to pay close attention to presidential debates despite technological advancements, the emergence of social media, and streaming platforms. In fact, two of the three most watched presidential debates in American history took place in 2016 (between Trump and Hillary Clinton and with 84.4 million viewers) and 2020 (between Trump and Joe Biden with 73.1 million viewers). Debating is in our DNA. Nealy three millenia-old, Homer’s Iliad begins with Agamemnon and Achilles squabbling over inherited authority versus talent. While Plato had opposed rhetoric to dialectic, his pragmatic student Aristotle compared the two.

Dialectic is primarily philosophical; rhetoric is political; dialectic comprises question-andanswer exchanges and the rhetoric of a predetermined speech. Debates have a profound history in American democracy. There was no moderator present during the seven inperson for the US Senate between Abraham Lincoln and Stephen A. Douglas in 1858! Each discussion was opened by one of the candidates in turn for an hour, followed by a oneand-a-half-hour rebuttal from the other contender, then a half-hour response from the first candidate to close it out. Howard K. Smith moderated the firstever televised presidential debate between John F Kennedy and Richard M Nixon in Chicago in 1960. The two candidates, however, never interrupted one another, launched personal jabs, or questioned one another’s mental health or allegiance to the country.

They never called the other person a clown, a liar, or even a socialist; they never even suggested that the other person was a radical Marxist or a covert fanatic. The inaugural debate between Governor Mitt Romney and President Barack Obama in 2012 demonstrates how respectfully and sporadically they interrupted one another. Has the debating culture become more crude, devious, and uncivilised over time, particularly in this posttruth era? In fact, things were completely turned upside down in 2016 after Trump and Clinton’s awful performances in their first debate in Las Vegas failed to inspire voters. Furthermore, many analysts deemed the first of Trump and Biden’s presidential debates in Cleveland in 2020 to be “unwatchable” because it frequently dropped to unexpectedly low levels. The altercation between the two candidates resembled a schoolyard brawl. The crucial query is, however, can presidential debates actually have an impact on changing voter behaviour? Overall, the answer may be basically “no.”

After analysing pre- and post-election surveys from 1952 to 2017, Vincent Pons of Harvard Business School and Caroline Le PennecCaldichoury of the University of California, Berkeley demonstrated that voter choice was not greatly impacted by televised debates. In a 2019 article, Pons was quoted as saying, “There’s this perception that debates are this great democratic tool where voters can find out what candidates stand for and how good they really are.” However, “we find that debates don’t have any effect on any group of voters.” Professors of communication at the University of Missouri, Mitchell McKinney and Benjamin Warner, examined survey responses from undergraduate students attending US universities between 2000 and 2012 and found that 86.3 per cent of respondents’ choices of candidates remained the same both before and after watching the debate.

Just 7 per cent of respondents, who were unsure, made a choice after watching the discussion, while only 3.5 per cent changed their opinions. Well, that could make a difference in a close contest! Who knows? It’s interesting to note that independents and undecided voters, who are most likely to be affected by the debates, are also the least likely to watch them. Indeed, those that watch debates are often among the most politically involved, so they probably already had their opinions formed before the discussion even started. For these folks, watching debates mostly serves as a spectator sport, with little to no impact on their opinions of the candidates other than seeing how their favourite performs.

The inaugural 2020 presidential debate was held on September 29. Voting analysis platform FiveThirtyEight’s average showed that, as of September 28, Biden had 50.1 per cent of the support while Trump had 43.2 per cent. On September 30, Biden’s percentage was 50.5 per cent, while Trump’s was 42.9 per cent. Similarly, there was little difference in the polling results before and after the second debate. On 26 September 2016, Clinton and Trump faced off in their tense first debate.

Most experts suggested that Clinton had dominated the debate. But according to FiveThirtyEight’s poll average, that performance barely moved the needle. On September 25, Trump’s percentage was at 40.5 per cent and Clinton’s was at 42.4 per cent. On September 27, Clinton’s polling position was 42.5 per cent, while Trump’s was 41 per cent. The same may be said of the other two 2016 debates. Nevertheless, debates are important because they reveal the issues that candidates value most, which gives voters hints about how to form their views. Reaction to debate issues and narratives generally drives the week after the debate. Crucially, there are still unanswered concerns regarding the likelihood that any opinion changes resulting from the debate will last.

The amount of postdebate campaign communication frequently overwhelms any discernible consequences of the events relatively fast. Furthermore, due to earlier access to ballots in different states, even small post-debate changes could be consequential in 2024. There have been instances, though, where debates have helped a certain candidate’s chances. Ask Barack Obama. In 2008, within a few days of the first debate on September 26, Obama managed to take a significant lead. The Pew Research Centre reports that shortly after the debate, Obama’s support increased to 49 from 46 per cent. This undoubtedly gave his presidential campaign more impetus. In actuality, presidential debates can affect voters’ perceptions of a candidate, as demonstrated by the cases of Obama in 2008 and Kennedy in 1960. Kennedy participated in four presidential debates in 1960 alongside Republican Nixon, who served as outgoing President Dwight Eisenhower’s vice president.

Though Nixon performed better among those who listened on the radio, a commonly accepted narrative that arose from those debates says that the younger, more vivacious Kennedy gained popularity over Nixon among those who watched the debates on television. According to a Purdue University study, one explanation for this could be that Kennedy “appeared better on television than Nixon.” Furthermore, despite the fact that debates typically have a small impact, 2024 has already shown to be different. Joe Biden decided not to run for re-election after his dismal performance in the June 27 debate utterly turned the race upside down.

A few minutes into the debate, the Democratic Party experienced a profound, widespread, and very aggressive panic. Immediately after the debate, some in the party started urging Biden to withdraw from the presidential contest. Though highly unusual, Biden’s withdrawal was a seminal event in American history. From a different perspective, that debate effectively shifted the momentum in favour of the Democrats, which would not have been straightforward perhaps had Kamala Harris been chosen at the outset! Whatever the situation, let’s enjoy how the fantastic four-year show has evolved.

(The writer is Professor of Statistics, Indian Statistical Institute, Kolkata.)