There's an old saying that there are no second acts in political life. This slight adaptation of a line written by the American author F Scott Fitzgerald means that a politician gets one big chance, and if he or she fails to deliver, then the public says goodbye and good riddance.
One example is the charismatic US presidential candidate Gary Hart, now the subject of a new Hollywood film starring Hugh Jackman. After years of service as the US senator for Colorado, Mr Hart emerged as the clear frontrunner for the Democratic nomination in the 1988 presidential election. However, his career ended in a storm of headlines about his debts and personal life.
The late British politician Enoch Powell – whose reputation has been comprehensively dismantled, thanks to his infamous comments about race relations – observed that “all political careers end in failure”. For many years, he was right about that, at least.
But in these difficult times – as Theresa May sits in number 10 Downing Street, unable to make sense of Brexit, and Donald Trump sits in the White House, unable to make sense even of his own personnel matters – some politicians from the past are being re-evaluated.
From 1993 until 2001, Bill Clinton presided over a booming US economy, a country largely at peace, and an America that, for all its imperfections, was admired around the world. Mr Clinton, nevertheless, will be remembered for lying under oath about the nature of his relationship with Monica Lewinsky.
As 2018 draws to a close, however, Mr Trump commands a deeply divided America and will not be remembered for one lie, like Mr Clinton, but a blizzard of thousands, according the New York Times.
In Britain, Tony Blair presided over mostly good times from 1997 until just before the 2008 financial crash. He helped bring peace to Northern Ireland in the Good Friday Agreement, greatly aided by the work of his somewhat underrated Conservative predecessor John Major.
Among other things, Mr Blair’s legacy has been blighted by the failures of the 2003 invasion of Iraq. But now both he and Mr Major are staging a quiet renaissance, thanks to Brexit.
Compared to the clumsy, embarrassing antics of Mrs May’s government and other British MPs, who daily seem in competition to show their ignorance about economics, geography, trade and world affairs, Mr Blair and Mr Major are emerging from the shadows as figures of reason.
A few days ago, I chaired a speech and news conference with Tony Blair. He offered positive ways to solve the problem of Brexit, and pointed out that only two possibilities exist. One is what he called a “painful Brexit”, the other a “pointless Brexit”. The pointless Brexit, he said, involves various schemes, including a so-called “Norway option” and Theresa May’s negotiated deal, both of which mean, in effect, leaving the EU, but in some way still being tied to its rules and regulations. In other words, Brexit in name only.
The “painful Brexit” would involve crashing out of the EU with no deal, trading under World Trade Organisation rules and causing unimaginable damage to the British economy.
Neither option commands majority support in parliament nor across Britain. Mr Major, while nominally a Conservative opponent of Mr Blair, offers a similar analysis in different words.
Both men are trying to be helpful. They want to ensure that Mrs May’s government avoids deepening Britain’s political turmoil into a genuine constitutional crisis.
In the past few days, even the Times newspaper, owned by Rupert Murdoch, has come round to the idea that giving the British people a final say via a People's Vote or second referendum might be the only way forward.
Mr Blair and Mr Major’s ideas point in the same direction. After his speech, Mr Blair was asked by a journalist how Mrs May can avoid the disaster that lies ahead. Mr Blair suggested that when a politician is in a hole they should “stop digging”.
Neither Mr Blair nor Mr Major are seeking a formal re-entry into British politics. But each is performing a great service to a country in difficulty. If Mrs May listens to them, she could conclude the first dismal act of her political life in something that falls short of total disaster.
If Brexit does go ahead next March, Britain will have no second act within the EU, unless we find a practical and constructive new way to re-engage with our closest and most important neighbours. With every day that passes, that task becomes increasingly urgent. After all, there is not much time before the final curtain.
Gavin Esler is a journalist, television presenter and author