An alternative articulation of this particular delusion is that the European Union is unreformable, and that the utopian goal is best achieved by collapsing the existing structures in the hope that something new and better will emerge.
The distortion of the terms of debate in the UK over its future and its role has been exacerbated by the globalisation of wealth and the further diminution of democratic accountability. Recent events have done nothing to reinforce any conviction that politicians and bureaucrats operate in the public interest. The paradox of the remain argument is that the risks and dangers of the exit option far outweigh the failings and urgent reform required in the EU.
Where the EU scores is not so much at the economic but at the social level. The limited rights of workers and the obligations placed on employers and governments may not satisfy the most vehement radicals, but they are a starting point for protection and regulation that goes some way to rebalancing away from the exploitative economic conditions that have been the focus of socialist ire for the best part of two centuries.
Europe has also been instrumental in environmental protection, which given the current direction of travel is another benefit that needs to be protected. The social and cultural hinterland of European engagement is a tangible benefit that the EU has supported and promoted, and the presumption of the rights of the citizen is distinctly un-patrician and precious in the context of a world where there is pressure to reduce every interaction to a monetised transaction.
On the larger-scale, as opposed to the individual rights secured, the EU has a better record of intervening in the interests of the wider community. It is typical that part of the exposure of British duplicity has been the revelation that the UK government has been undermining efforts to investigate, regulate and close down tax avoidance in offshore schemes, which the majority of EU members have been pressing for.
Nobody who supports the EU would argue that its development has been smooth, optimal or that its current political and institutional structures are right. The headlong rush to expand into the emerging eastern democracies might have been handled better - and the approach of ultra-orthodox adopted by the northern states during the 21st century depression had vile and unintended consequences. There is a democratic and engagement deficit. Yet this is not enough to argue against the European ideal nor efforts to achieve there.
Cornyn's belated endorsement of the remain campaign is welcome, as it demonstrates both realism and the calculation that there is a majority of mainstream opinion in favour of continued membership. Changing the EU is best done from within, and with enthusiastic support for the wider ideal. Even Cameron has edged towards this position.
The left-wing Europhobes are sincere and well-intentioned, which is probably more than can be said for many of the motley crew of has-beens and xenophobes leading the right's charge. Yet they resemble the Trotskyites of the 1980s, preferring to spar around purity and factionalism rather than turning the fire on the enemy, who are the unfettered neoconservatives whose objective is not merely to leave but to dismantle the rights and benefits that are guaranteed through the commitments required even under the current flawed Union.
EU membership is, in the scheme of things, central to citizens' interests, but peripheral to the debate as to what sort of society we are looking for. The delusion that leaving will make achieving the latter is a gift to opponents not just of Europe but of a better society. Time to reflect, and ensure that the minor divisions on the centre and left are not exploited by the right in its Machiavellian strategy to deny the damage and lunacy of much of its anti-European campaign.