They say the secret to happiness is low expectations. In which case, Donald Trump has been doing his Democratic rival a big favour. In advance of next week’s debate — the first of three — the US president has all but diagnosed Joe Biden with dementia.
The former vice-president “doesn’t know he’s alive” and “can’t put two sentences together”, according to Mr Trump. It follows that all Mr Biden need do is sound vaguely coherent.
But the Democrat will have to do more than that to shift the polling numbers. In spite of the razzmatazz, US presidential debates only rarely change an election. Some of the most cited moments, such as Richard Nixon mopping his brow in the first televised debate in 1960, or George HW Bush impatiently consulting his watch in 1992, had only a limited effect. The first Biden-Trump debate may prove to be an exception.
Should Mr Biden slip — with one of his trademark gaffes, for example — the election could become about him, rather than a referendum on Mr Trump, which is where Democrats want to keep it. The two debates that have arguably changed a presidential election — Ronald Reagan versus Jimmy Carter in 1980 and Al Gore versus George W Bush in 2000 — show what is possible next week.
Mr Gore had an edge over Mr Bush in the autumn of 2000, which he lost in the debates. His errors were despairingly trivial. The outcome had very little to do with their contrasting tax and spending proposals, or the future of US foreign policy. Rather, it boiled down to the split TV screen that captured Mr Gore sighing and rolling his eyes every time Mr Bush was talking.
Here was an object lesson in how voters decide. Swing voters said they would prefer to have a beer with the teetotal Mr Bush than his condescending opponent. Mr Biden should take note. The temptation to throw his arms up, or spontaneously combust, every time Mr Trump lies will be hard to resist. On facts and preparation, Hillary Clinton got the better of Mr Trump in all three 2016 debates. She still didn’t win.
Reagan’s task in 1980 was to convey that he was sane enough not to blunder into a nuclear war with the Soviet Union. He was under related pressure to show he was not senile. At the time, he was, aged 69, the oldest potential commander-in-chief in US history. Mr Biden is 77, the same age as Reagan at the end of his second term. (Reagan was 83 when he was diagnosed with Alzheimer’s.) Mr Biden’s task is also simple: to show he has the presence of mind to be the moderate president he says he will be, thus deflating Mr Trump’s claim that he is the “helpless puppet of the radical left”.
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Reagan’s is the example Mr Biden should want to emulate. By clearing the sanity bar — “there you go again” was Reagan’s jovial retort every time Mr Carter painted him as an extremist — he gave millions of waverers the confidence to vote for him. He closed the only debate between the two by looking into the camera and asking: “Are you better off than you were four years ago?” The answer in 1980 was obviously no. The question is just as relevant for Americans today.
No two incumbents are less alike than Mr Carter and Mr Trump. The culture of civility that Mr Biden wants to restore was buried in the last election.
In the 2016 debates, Mr Trump threatened to jail Mrs Clinton if he was elected. He said she had “hate in her heart” and was an enabler of her husband’s alleged sexual harassment (Mr Trump invited four women who made claims against Bill Clinton to come to the second debate although his efforts to seat them in the VIP area were thwarted). He appeared to have no idea of what a “no first use” nuclear policy meant and falsely claimed that the US had let in millions of Syrian refugees. Any of these mistakes could have destroyed a candidate in an earlier era.
What taboos will be broken next? Mr Trump has belatedly tried to alter expectations by claiming Mr Biden is taking performance-enhancing drugs. Perhaps he will allege that on live TV, or mock Mr Biden for showing up in a mask. For sure, he will flood the zone with falsehoods. “There you go again,” might have worked as a riposte in 1980. It will not be enough in 2020.