Launching Reform UK’s latest attempt to look like a party of government, rather than a gang of populist rabble-rousers, its Treasury spokesperson Robert Jenrick shamelessly invoked the unimpeachable liberals John Stuart Mill and William Beveridge.

Neither that effort at intellectual respectability, nor the other highly discriminatory and counter-productive measures announced, were credible. To the extent that they would save as much as intended, they would do so by imposing much misery on the most vulnerable in society; and they would substantially weaken the British economy as a whole, and thus the prosperity of all, by reopening the whole Brexit debate and fracturing trade with the European Union.

It proves, once again, that when people think of voting Reform UK as a “last throw of the dice”, it is indeed a gamble. It is increasingly clear that it would be a reckless one, too.

Take the much-quoted Lord Beveridge, who produced the 1942 report on social insurance that formed the basis for the modern welfare state. Repeatedly, Mr Jenrick praised the Beveridge principle of “contribution” as a way to balance personal responsibility and collective, or social, security. As the ambitious Reform front-bencher sees it, the present social security system breaks that “bond” between contributions and benefits.

Yet he proposes to set that asunder even more, by removing people who are working in the UK – and thus paying their taxes and national insurance contributions – almost entirely from the welfare system, and particularly universal credit.

This makes no sense. A family from, say, Spain or Pakistan with parents at work and children at school, effectively settled in Britain, will pay the same taxes and national insurance as the “British” family next door, yet have zero entitlements to a whole range of social security benefits, even though they have been “paying into the system” for years and will expect to do so for decades longer.

The Reform policy paper is unequivocal: “Under Reform, only British citizens will be entitled to almost all benefits. In particular, we will restrict access to universal credit, housing benefit, most other non-contributory benefits, and taxpayer-funded free childcare to British-citizen adults. These rules will apply to both new and existing claimants.”

There is an insidious assumption here that all “foreign nationals” are spongers, and that only the British are hard-working and deserving. This is nonsense. The social security system isn’t a national charity for the deserving poor, but something that holds society together. The universal credit scheme, for all its manifest flaws, was designed to remove disincentives such as “poverty traps”, so that people take on work and contribute to the national income. That applies whatever passport someone has.

If they are not to have the same entitlements as their British neighbours, then logically they are due a substantial tax rebate. It is also worth adding that Reform have always said they will also make it more difficult for “foreigners” to gain British citizenship on principle; their welfare reforms add a financial incentive to withhold it. So much for integration, then.

Another practical weakness in the Reform proposals – the party is not so moved by accusations of cruelty or discrimination as such – is forcing employers with more than five staff to take on the role of the state in social insurance and health care. This looks like a stealthy step towards privatisation.

Apparently based on a Dutch scheme, it must carry with it the risk of a significant increase in cost and managerial “pastoral” responsibilities for ill staff most companies are surely unwilling to take on, even with the tiny tax breaks offered by Mr Jenrick. The net effect would be to make employers even less willing to take on people with long-term conditions, or who they perceive as liable to develop them.

Thus the policy is self-defeating – preventing people from moving back into work. Reform say they will impose strong anti-discriminatory laws to combat this, but that is against their usual instincts towards deregulation. Even if sincere, it would be difficult to enforce.

Even if the £50bn-a-year in unlikely savings postulated by Reform came to pass, it would be dwarfed by the damage inflicted on the economy, and thus tax revenues, by “more Brexit” – their most pernicious policy, and the one they’d pursue with all the passion their unnatural, visceral Europhobia suggests.

A mutual, reciprocal recognition of UK and EU citizens was the first thing that was agreed to by then prime minister, Theresa May, and rightly so. To dissolve that now would mean years of acrimony and uncertainty at best; and, more likely, irreparable damage to experts, jobs, and – at the end of the process – to UK national security.

The British welfare state certainly needs reform, not least because Brexit so weakened the nation. But it does not need this kind of reform, and – to borrow a phrase – the UK really doesn’t need Reform.