Political outsiders flourish in much of the western world. The most prominent and unorthodox, US President Donald Trump, hopes to win a second term next year.
The UK is about to leave the European Union partly as a result of relentless campaigning by one person – Nigel Farage – an outsider of such purity he has never been a member of the British Parliament. Even in countries such as Germany and Austria, still haunted by the traumas of the 1930s, the far right stirs.
In contrast, liberals who once ruled with confidence are in bewildered retreat.
At least that appears to be the overwhelming pattern of the decade. Yet the picture is a little more complex than it seems. Take a closer look and when some of the seemingly dazzling outsiders come close to power they run away speedily. The outsiders tend to like campaigning but not the responsibility and hard grind of implementing policies.
After the far-right Alternative for Germany (AfD) party secured seats in the Bundestag for the first time, its leader resigned immediately.
After the Brexit referendum in the UK, Mr Farage, then the leader of Ukip, took a bow and became a radio phone-in host. The thorny Brexit negotiations were left to others as he looked on from the cosiness of a studio.
In Italy, representatives of the Five Star Movement won some spectacular victories but struggled subsequently.
One leading figure, Mayor of Rome Virginia Raggi, was stripped by her party of the power to make "important decisions" after a close adviser was arrested for suspected corruption.
Even those who acquired power or rose spectacularly to lead potential parties of government failed in fundamental ways. Alexis Tsipras, Greece's former left-wing prime minister – elected sensationally in 2015 for opposing austerity measures being imposed by the EU – almost immediately agreed to deep spending cuts. In the UK, Jeremy Corbyn became Labour's most left-wing leader in years, against his own expectations. But after two general election defeats he announced that he would stand down when the party chooses a replacement.
The rise of populists and the failure to make the most of the opportunities that arise from electoral success are unsurprising. After the global financial crash in 2008 caused by the banks, disillusionment with mainstream politics deepened. Trust was already fragile, but suddenly voters felt powerless as banks headed towards bankruptcy but were bailed out by governments borrowing billions.
Before the crash, bankers were revered in much of the western world. They were hailed as the great wealth creators. If ambitious politicians sought to prove their credibility, they would be photographed with a banker. After the crash, bankers came to symbolise the greedy criminality of "elites". The elected politicians were despised for being part of a system that spiralled towards calamity.
From left to right, outsiders represented new ways of leading. They were protectionists who "put their countries first". They would intervene in markets. They would spend more. They would stop the movement of people, a message that became more potent as asylum seekers and migrants rushed towards more prosperous regions.
Mr Trump won partly by promising to build a wall between the US and Mexico. A major factor in the popularity of Brexit was opposition to the free movement of labour.
Conversely, German Chancellor Angela Merkel suffered a big drop in support when she allowed large numbers of asylum seekers from Syria to come to Germany.
Yet in spite of these volcanic forces propelling outsiders towards electoral success, Mrs Merkel remained in power as a long-serving chancellor. In France, President Emmanuel Macron comfortably dispatched Marine Le Pen and her far-right party.
In this year's British general election, Mr Farage could not find a seat he was confident of winning and therefore did not stand. The mainstream hangs on in there.
There is a fundamental reason why outsiders have not made more of their electoral successes. Only in politics is total inexperience a positive qualification. If someone walked off the street and asked to play Hamlet, a director would insist that some past experience of playing lead roles would be required.
If political outsiders deride Washington, Westminster or Berlin and proclaim an unfamiliarity with politics, they are in with a big chance. But soon they discover that governing is incomparably more difficult than campaigning.
The outsiders do not know how to govern.
Nonetheless, the rise of nationalism and cruder forms of populism continues to make its mark on western democracies with potentially even more tumultuous consequences to come.
In the recent UK election, the Scottish National Party came close to sweeping the board. The chance of another referendum in Scotland on independence from the rest of the UK is extremely high. An insular English nationalism linking elderly voters in the affluent south with poorer voters in the north of England fuelled Brexit and will assume more triumphalist forms now the UK is definitely leaving.
Right-wing populists might not be at ease with the complexities of government but they remain a potent force. In Germany, the AfD has become the biggest opposition party in the Bundestag. In Spain, Vox is now the third-largest force in Parliament. In part, voters are frustrated with the political establishment but they also have concerns about globalisation, immigration, a dilution of national identity and the European Union. In the European Parliament, nine far-right parties have formed a new bloc, called Identity and Democracy.
Globalisation, changing work patterns, the movement of people and the revolution in communications have made voters much more insecure and less trusting of those they elect.
Mainstream parties have only started to address how governments can intervene to protect voters from the new fragilities arising from a global economic market and a technological revolution. Outsiders have simplistic answers that have a compelling accessibility in an era of angry mistrust.
The constant factor of the decade is voters' disdain for elected politicians. It looks as if this will be unchanging in the coming decade too.
Steve Richards’ book, The Rise of the Outsiders, is published by Atlantic