The smallest denomination of US currency, the one cent coin, doesn’t buy much, but it does provide a glimpse of how Americans like to see themselves. Every coin carries the Latin phrase “E Pluribus Unum", which translates as “out of many [people], one [nation]”. It’s a tribute to the unity in diversity of 350 million Americans and their migrant history. But the phrase is not a statement of fact about unity. It’s an ambition. This ambition historically has often not been achieved because America – like now – has always had to contend with its deep and sometimes violent divisions. In the 1770s, the British colonists were split between those who remained pro-British and the rebels who created the United States. In the following century what Americans in the southern states called “the peculiar institution” of slavery led to the country almost falling apart. President Abraham Lincoln, a Republican, was gracious in victory as his Union troops crushed the Confederacy in the Civil War. He promised in his second inaugural address in 1865 a renewed union with magnanimous words carved on the walls of Washington’s Lincoln Memorial: “With malice toward none; with charity for all; with firmness in the right, as God gives us to see the right, let us strive on to finish the work we are in; to bind up the nation’s wounds.” Now more than a century and a half later, the Democrat who will be the 46th president needs once more to bind up the nation’s wounds. As his defeated opponent Donald Trump sulks in the White House, Joe Biden called for an end to "the anger and demonisation" in politics saying that "the vast majority of the 150 million Americans who voted – they want to get the vitriol out of our politics". In phrases that Lincoln himself might have used, Mr Biden spoke of a new coming together: “The purpose of our politics isn’t to wage total and unrelenting war. It’s to solve problems. We may be opponents but we’re not enemies. We’re Americans.” Yet healing did not work for Lincoln. He was assassinated by a Confederate diehard, John Wilkes Booth, who shot him in a Washington theatre. For Mr Biden his statesmanlike declaration of coming together will not be easy to put into practice. It may not be possible. There are 70 million Trump voters, some of them irreconcilable, some armed, and a few potentially dangerous. The culture-war wounds of post-Trump America are deep. Trumpism as a phenomenon will outlast Mr Trump himself since it is based not just on the votes of those 70 million but on decades of genuine grievance as well as bitterness and bigotry. Despite all the froth, lies, nasty comments, and divisive tweets from the White House over the past four years, Mr Trump did not cause America’s deep divisions, but he was elected as a result of them. He has repeatedly exploited the fault lines in a society divided over wealth, privilege, opportunity, culture, race, and even the meaning of America itself. Is the US, as Ronald Reagan put it “a shining city on a hill", a beacon for the rest of the world? Or is America “fortress America", where generations of politicians have put “America first", suspicious of “foreign entanglements", in which Mr Trump promised to “build that wall” and make Mexico pay for it? (He didn’t succeed, by the way.) Even in the greatest struggle of the 20th century, the Second World War, the US was so divided between those two visions – the beacon and the fortress – that president Franklin Roosevelt could not lead his country into war. It took the attack on Pearl Harbour by Japan in December 1941 to bomb the US out of isolation and into defeating fascism. Faced with the clear enemy of Soviet communism in the 1950s America was split again. The McCarthyite witch-hunt ruined the lives of those deemed not sufficiently patriotic. In the 60s and 70s, racism, civil rights and the Vietnam War exposed again the fault lines in American society. By the 90s, with the collapse of the communist threat, America was left as the world’s only superpower but turned inward again to its own quarrels. From the moment Bill Clinton was elected, he and his wife Hillary were hate figures for the far right. Republicans in Congress conspired to destroy the Clintons, spending years investigating their supposed shady property deals in Arkansas, the so-called “Whitewater Affair". Whitewater yielded nothing, so they switched to Mr Clinton’s sex life. Mr Clinton became only the second president in American history to be impeached. Twenty years later, Democrats got their revenge by impeaching Mr Trump. Both presidents survived the process, but the country remained deeply split. The United States, in other words, is always diverse but also divided. For Mr Biden, healing is Job One, but healing now is made more difficult by Mr Trump’s hissy fit, his childish refusal to accept defeat compounded by baseless claims that the election has been “stolen”. The Senate, like the country, is divided down the middle. Rural America and urban America often seem like different nations. Race remains America’s original sin. There, however, are reasons for optimism. First – and this is meant as a compliment – Mr Biden can afford to be dull. Rather than the political performance art of Mr Trump, Mr Biden can be steady. He will re-engage with Nato, the Paris climate agreement and the World Health Organisation, and restore a calm America that can truly lead on the world stage. As vice-president, Kamala Harris, a woman of Jamaican and Indian descent, is a living, breathing, human example of “E Pluribus Unum". Bipartisan action on the coronavirus pandemic and foreign policy will be good for every American. And if a nation as vast as the US can be said to have a “mood", there is a sense of exhaustion about America’s divisions. Many Republicans, privately, will be pleased the Trump tantrums no longer define their party. Congressional elections are every two years and voters will not forgive Republicans who offer more division. One further reason for optimism comes from the Irish writer Oscar Wilde. He quipped that “the youth of America is their oldest tradition. It has been going on now for three hundred years. To hear them talk one would imagine they were in their first childhood. As far as civilisation goes they are in their second". Beneath the sarcasm, Wilde has a point. America has coped with divisions for several hundred years. No other country – France? China? India? Russia? – captures the imagination of the world the way America does. Mr Biden will not bind up all America’s wounds. But he will try. Being able to change profoundly is also one of America’s oldest and best traditions. And so is hope. <em>Gavin Esler is a broadcaster and UK columnist for The National</em>