They haven't got the hang of Nigel Farage and Ukip, that parody of a party.
Ridicule them, expose them, assail them, confront them with facts: assaults that would cause lethal injuries in the normal run of politics serve only to make these insurgents stronger.
There's a certain logic to it. If you take the view that the Westminster parties are not credible, why would attacks from these parties be credible? If you accept, with Mr Farage, that a corrupt elite is doing a good man down, why not side with the plucky underdog?
You have to suspend a lot of disbelief to get to that point, of course. Above all, you have to buy the standard Farage excuse that Ukip's problems stem from just a few obnoxious oddballs who have entered the ranks because a poor little party lacks the means to screen candidates. The barrel, runs the claim, only seems to be overflowing with rotten specimens.
Remarkably, plenty of English voters seem happy with that wafer-thin excuse. Mr Farage is very close, in fact, to pulling off the trick once accomplished by the Tea Party crowd in the United States. If you turn "mainstream" into a dirty word, any criticism from that quarter, whether in the media or in politics, only confirms your virtue.
Patently, Mr Farage is an opportunist. He keeps things simple to an extent that ought to be insulting. More often than not, he talks rubbish with a fair dash of hypocrisy. But he gets away with it for two obvious reasons. First, the dominant Westminster parties are held in disdain with very good cause. Secondly, English politics provides few enough alternatives to voters.
With European Parliament elections due on May 22, the second of those facts is easy enough to illustrate. The Green Party is attempting to carry the fight to Ukip, without too much success, while the main parties are showing symptoms of panic. In England, the struggle for top spot is between Labour and the ramshackle forces of Mr Farage, now nominated, in this context, as "the alternative". As a comment on the condition of the body politic in the south, that's hard to beat.
Research by Scottish Centre on Constitutional Change at Edinburgh, Cardiff University and the Institute for Public Policy Research (IPPR) tells the story. It's a big survey containing several messages, one about English politics, one about the state of those "mainstream parties", one about the evolving nature - and the sustainability - of this purportedly United Kingdom.
Ukip has a 29% share of English voting intentions, seven ahead of the Conservatives and just one point shy of Labour's tally. In Scotland, Mr Farage and his troubled organisation muster just 10%; in Wales only 20%. But this is more than evidence of an anti-immigrant, anti-EU faction exploiting a desire for protest, or proof of the bizarre theory, beloved in some quarters, that Plaid Cymru and the SNP are somehow Ukip equivalents. This has to do with Tory England.
Proponents of the Union dislike this notion. They would have us believe that differences in political and social attitudes between parts of the UK are hardly worth mentioning. The Edinburgh-Cardiff-IPPR (Independent Public Policy Research) work says otherwise. Only in England does the combined Tory-Ukip vote achieve a majority, amounting to a remarkable 51%. For Wales, the joint figure is 38%; for Scotland, 22%. Adduce any reason you like, the divergence is stark.
Granted, European elections are at stake. Special circumstances - not to mention more apathy than usual - need to be borne in mind. But when the survey delves into attitudes towards Ukip, a sense of a distinctively English polity emerges. Is Mr Farage the politician who "best stands up for the interests of Scotland"? Only 1% of Scots answer that slightly comical question in the affirmative. In Wales, the equivalent figure is 3%, in England, it's 20%.
Such is the nature, like it or not, of politics south of the Border. If the electorate does not lean rightwards, it has a funny way of demonstrating otherwise. Between them, the Tories and Ukip account for 39% of the "best stands up for England" choices. Labour manages 17%, losing out to the 19% who maintain that no party stands up for that country.
You could state it otherwise. Ukip, without a single MP, together with the "no party" declaration, account for 42% of the English vote. Labour, the Tories and the LibDems combined manage only a collective 37% prepared to say these parties best represent the people of England. The country simultaneously inclines to the right, but mistrusts its political establishment profoundly. So Mr Farage prospers.
As he would put it, he is also, so it seems, winning the argument over "Europe" much as he won his risible TV debates with Nick Clegg. Should David Cameron ever get around to his in-out referendum on EU membership, 40% of English voters would vote to quit. With 37% content to remain within that union, the argument is far from lost, but the contrast with Scotland is - or ought to be - startling. Of voters here, 48% would remain in the EU and 32% would choose to leave. If that's not a divergence in political cultures, what is?
The prospect of Mr Farage emerging from the European Parliament elections with a refurbished smile does not offer much cheer. The inevitable reaction from the Tories and Labour is even less inspiring. Conservative euroscepticism will become frenzied and not a single MP will pause to think twice about 48% of Scots, their interests or desires. Labour pandering over immigration - the real meaning of "Europe" for Ukip's followers - will continue apace. Personally, I wouldn't wish those outcomes on folk in the south. On the other hand, the political choices being made are not truly my business. The existence of a phenomenon called Tory England, right-wing England, is another matter. Ed Miliband seeks to deny that it exists, for he must, but the survey results say otherwise. Election results say the same. So what happens to the rest of us if Mr Farage marches on, or if he is stopped by party political appeasement?
Perhaps I should urge the voters of England to reject Ukip and all its works as an act of solidarity. How would that go? Perhaps Scots should merely shrug when a big chunk of the dominant electoral group in these islands decides that there's nothing wrong with Mr Farage's unpleasant hokum. That's how the system works, after all. If the survey is correct, Scots are these days outnumbered by supporters of Ukip. That's democracy. Of a sort.
Democracy is in fact hard to define within an asymmetrical constitutional arrangement. So Mr Farage ploughs his furrow, induces Labour and Tories to come chasing behind, is rejected utterly in these parts, and all of this is as it should and must be? That excuse for reasoning will not survive for much longer no matter what happens in September's referendum.
When the people of England speak, they speak for themselves. Judging by the survey, around 35% regard themselves as "English only" or "More English than British". That's fair enough. But we had better attend to the consequences.