For a study in political pathology there are few more promising subjects than the UK Independence Party. Here is a political grouping, as its leader, Nigel Farage, never tires of reminding the world, that emerged from nowhere to change the British constitution and, quite possibly, the future course of European history in an unpredictable but undoubtedly profound way. Once they were merely the subject of curious amusement: “Well, you’re not laughing now”, Mr Farage told the European Parliament on the morrow of his triumph.

Sadly, the world is laughing at Ukip once more. Between altercations, the shortest recorded leadership, or, technically, almost-leadership, of a major party, to the falling away of the talent that could possibly rescue the party from ridicule, the comical pratfall is complete. In the latest development prospective leader Raheem Kassam has ducked out. He certainly carried some baggage with him, but he was at least forthright and attention-grabbing in a Farage/Trump sort of way. He claims, in an echo of the short-lived leader-elect Diane James, that he is not “satisfied about the integrity of the process” and that “the path to victory is too narrow”. That suggests that there is something systemically wrong with Ukip. Paul Nuttall, Suzanne Evans, John Rees-Evans and Peter Whittle remain in the fray, for what it’s worth.

Ukip matters most not because of the strength of the party itself – and arguably its main work is already done. It matters, rather, because of the unpredictable and potentially game-changing effect Ukip has on the fortunes of the main parties. At the last election it only managed to win one parliamentary seat, thanks to Britain’s ruthless first-past-the-post voting system, but it did garner some 3.9 million votes. Ukip also scored a high number of second places, especially in areas traditionally loyal to Labour, along a long swath of the East and North of England. It has even enjoyed some unexpected success in Wales. The political and economic events of the next few years look unusually unpredictable, but they could offer Ukip a chance to build on the substantial electoral success it enjoyed in 2016, as well as in this year’s referendum.