Moreover, Trump taps into political trends that go way beyond him -- beyond America in fact. His success so far reflects broad dissatisfaction with both the priorities and the process of contemporary politics. A revolt is under way that defies old-fashioned ideals -- like compromise and reason.
Consider how things have changed in my home country of Britain. Elections used to cleave to the center-Right Conservatives and the center-Left Labour Party. In the last five years, however,
we've suddenly gained a multiparty system. Scots overwhelmingly vote for the separatist nationalists, who are also socialist. The environmentalist Greens have a voice in Parliament. There is a Trump-style movement,
called the United Kingdom Independence Party; it calls for independence from the European Union and controls on immigration.
And Labour is undergoing a leadership contest which may well be won by Jeremy Corbyn, a bad tempered
, hard-left candidate who wants to nationalize the energy sector and scrap our nuclear defense.
The British are as amazed by Corbyn's popularity as the world is by Trump's
. In the same way that the Republicans probably need to move to the center to win in 2016, Labour does itself no favors by flirting with socialism.
A few themes unite Trump and what's happening in Britain. One is the cult of the amateur. For too long, our politics was dominated by people who seemed to be replications of each other: smiling white men in crisp suits with great hair, great teeth and no biography beyond politics. T.S. Eliot's hollow men.
So the British have now flocked to people who seem more ordinary, less spun. The Scottish nationalists are led by a working-class woman who recently wowed everyone on "The Daily Show
." The UK Independence Party (Ukip) leader is an affable fellow who breaks all the rules by smoking. And Jeremy Corbyn doesn't wear a tie.
The great thing about amateurism is that the media leaps on mistakes but, unusually in politics, the public doesn't condemn them. On the contrary, they are an affirmation of ordinariness. If Bush or Walker called Rosie O'Donnell a "pig", they'd see their poll numbers drop. But the insult only makes The Donald more popular.
A second unifying principle is the rise of sectional voting. There used to be broad understanding of parties as coalitions within which there is give and take. In Britain, Labour contains ideological socialists, social democrats, liberals, trades-unionists, civil rights activists, feminists etc. In the U.S., Republicans have been home to New England liberals, Southern traditionalists, low-tax conservatives, religious conservatives, neoconservatives etc.
The belief in times past was that if a leader could unite and expand that coalition then he or she could command a majority in the country and govern according to a program of broad national consensus.
But, increasingly, party activists aren't interested in that. Now there's a preference for defining a party's ideological core and refining its leadership to the point of purity.
We saw this gathering momentum
during the tea party insurgency of 2010-2012, and it's happening again through Trump. Support for Trump is not just about letting a conservative view on immigration be heard. It's about breaking the leadership of the party, whipping moderates into line and creating a purer GOP.
If the result is defeat in the general election then who cares? Not Trump,
who has refused to rule out a third-party candidacy even though it would hand the presidency to Hillary. There's a comparison to be made with Jeremy Corbyn's leadership campaign, which has also ranked principle above electoral expediency.
Defeat doesn't much bother them. They just want their party back.
Finally, Trump stands for nationalism. His favorite talking points are the "criminality" of illegal Mexican migrants and the cunning of the Chines
e. His populist positions exploit that other cri de coeur of our era: "Who will put me first?" As the value of national consensus has declined, along with parties that seek to represent the whole nation, so the needs of the individual voter and their local community have been prioritized.
Scottish nationalism, compared to Trump, is left-wing and multicultural -- but still inward-looking and still fixated on the wickedness of outsiders (in their case, the English). And while Jeremy Corbyn's socialist insurgency is very pro-immigrant
, it is also anti-NATO and in retreat from the realities of globalization. Corbyn offers to put the British working-class first, even if his understanding of their economic needs is rather different from Trump's.
Of course, all of these comparisons come with caveats. Britain and America are different in so many regards: the richer Trump declares himself to be, the cheaper he sounds to the English. And none of these themes are really unique to our era: Trump bears comparison with Barry Goldwater and H. Ross Perot.
But while anger at elites is a permanent fixture, even a healthy one, of democracies, there is a very particular kind of rage in 2015.
It feels as though the economy isn't working in everyone's interests and politicians are only working in their own -- a mood exacerbated by the credit crunch and Barack Obama's failures in office. A lack of strong centrist leaders ultimately creates the vacuum that radicalism fills. Blame for Trump lies as much with Bush, Walker, Christie or even Clinton as it does The Donald himself.