When two of my favourite commentators on current political events, Ian Dunt (ID) and Owen Jones (OJ), cross swords, albeit briefly twitter style, the chance is that there maybe something interesting going on. I can see what I suspect annoyed OJ in ID’s piece, but I think OJ’s response was too easily sidetracked in the confusion that is history. I am going to stay on more familiar UK (and US) ground.
The general theme is ID’s piece is totally laudable. It is essentially a warning against populism of the type Jan-Werner Müller describes, and which is embodied in Viktor Orban’s Hungary. I also think he is almost right when he writes:
“Every constituent part of the Orban programme exists here: the anti-semitism, the focus on Soros, the relentless fear-mongering about immigrants, the demonisation of the EU and its institutions, the attacks on Islam, the undermining of an independent judiciary, and, most of all, the widespread conspiracy-squint - the idea, popular on left and right, on almost all matters of political consequence, that shadowy and powerful forces are undermining the people's will.”
I say “almost” because this is an undifferentiated list, and the emphasis is put on what I regard as least important. For Müller populism is a moralised form of antipluralism. The populist politician talks about the “will of the people” even when the people may be just a subset of the population, but the wishes and beliefs of the remainder are of no weight and are not acknowledged. They become instead the enemy within. To overcome that enemy within (be it Jews or Muslims or liberals) and the enemy outside (the EU trying to force Hungarians to accept immigrants), the leader needs total control, which means subjugating an independent judiciary, an independent press and other independent institutions. For Müller, populism is an attack on pluralistic democracy, attempting to replace it with some kind of autocratic or plutocratic democracy. Orban’s Hungary has so far been a very successful (in terms of longevity) example of this form of populism.
Where I started to disagree with ID’s piece is where he tries to do the classic centrist thing, which is to imply that the dangers of populism in the UK come from both left and right. In immediate historical terms this is nonsense. Immigration as an issue was revitalised by the Conservative opposition and the right wing press in the early years of the Labour government. In 2001 William Hague talked about Tony Blair wanting to turn the UK into a ‘foreign land’. The right wing papers started producing negative stories about immigrants, long after the rise in non-EU immigration in the late 1990s and long before the rise in EU immigration from 2004, and popular concern about immigration rose with this increase in press coverage. The best explanatory variables in explaining concern about immigration were readership of the Mail, Express and Sun, in that order. All three were better predictors of concern about immigration than whether people voted Conservative.
When the Conservatives became part of the coalition government in 2010, this emphasis on immigration became official policy. By now the idea that immigration was ‘a problem’ that needed to ‘be controlled’ was firmly entrenched in political discourse. Conservatives found it attractive because it could persuade socially conservative left wing voters not to vote Labour, and because it became a useful scapegoat for the effects of austerity. The right wing tabloids also found it attractive because it became a means of winning the Brexit vote. And it is Brexit where we have seen populism in full force in the UK: talk of the ‘will of the people’ as if the 48% who voted Remain did not exist, attacks on the judiciary, on the civil service, on parliament and on universities. The EU is the enemy without, and Remainers are the enemy within.
To the extent that populism has come to the UK, it has come from the political right, not the political left. Yes Labour in government eventually felt they had to play along with the immigration problem theme, and yes there are Lexiters on the left. But the motive force for attacks on immigration and Brexit comes from the right, not the left. 
Much the same point can be made about the US. Trump was voted into office as a Republican, and he remains unchecked in office because of the Republican party. To suggest that Republicans and Democrats bear equal responsibility for Trump is just nonsense.
In this story of how populism came to the UK, and represents an ever present threat in the UK, Labour’s problems over antisemitism do not even deserve a footnote. Antisemitism is a big part of Orban’s campaign and rhetoric, personified in his constant attacks on George Soros, but that theme has been repeated not by Corbyn but by the same right wing press that focused on immigration and gave us Brexit. Antisemtism is a problem within Labour, but the source of that problem is the Israel Palestine situation. It is not, and never will be, a part of a Labour government’s appeal to the electorate. It will not be a Labour government that tells people that have lived here for scores of years that they now have to leave the UK and say goodbye to their friends and family. It is not and never will be the Labour party that runs an Islamophobic campaign for mayor of London.
In Europe and the US, the threat today of an authoritarian, anti-pluralist government comes exclusively from the right. To lose sight of that makes dealing with that threat much more difficult.
 There are plenty of centrist Remainers who insist Brexit is as much Corbyn’s fault as it is the government’s. Apparently the fact that Corbyn campaigned for Remain does not count because he didn’t put enough energy and passion into that campaign. When he says he would vote Remain again he must be lying because no one ever changes their mind. Accusing Corbyn of being too ready to accept the referendum result is fine by me, but to put him in the same class as Johnson and Gove is just token centrism.