Every test shows this Brexit deal is the best

LIKe every economic forecast ever attempted, yesterday’s treasury figures on the impact of Brexit should be taken with a large pinch of salt.

After all, these same crystal ball gazers got it spectacularly wrong on the eve of the referendum, when they predicted that a vote to Leave would cause an ‘immediate and profound economic shock’.

even before we pulled out of the eU, they said, unemployment would rocket within two years by between 500,000 and 800,000.

Well, more than two years have passed since the public ignored Whitehall’s scaremongering and opted to withdraw. Since then, the economy has grown steadily (no sign of that recession yet), while the jobless figures have hit record lows.

So, no, nobody should treat the treasury’s predictions as Gospel. With so many unknowns to be factored in – from Donald trump’s maverick trade wars to extreme weather events – it is simply impossible for even the most gifted futurologists to foresee with any accuracy what might happen 15 months from now, let alone 15 years.

Still less should the public be unduly alarmed by the Bank of england’s ‘stress tests’ for the financial sector. these are not based on predictions of what is likely to come about. they are designed merely to answer the question: ‘If the very worst were to happen, could the banks cope?’

to that extent, we may draw comfort from Governor Mark Carney’s conclusion that all UK banks are now strong enough to survive, come what may.

But though the figures in the treasury forecasts may be untrustworthy – and the Bank’s war-gaming open to misinterpretation (not least, by the alarmist BBC) – it would be deeply foolish to dismiss yesterday’s warnings.

For they are hugely valuable in subjecting different types of Brexit to the same tests, so that comparisons can be drawn between them.

the fact is that of all forms of Brexit, theresa May’s deal offers a real hope of continued prosperity, with the least economic and political disruption.

As for crashing out with no deal, this would be the worst outcome of the lot. In Mr Carney’s words, it would cause more harm than the financial crash ten years ago.

But don’t take the Mail’s word for it that Mrs May’s deal deserves wholehearted support. Listen to prominent Brexiteer Jim Ratcliffe, boss of the chemicals giant Ineos, who yesterday joined other business leaders in calling on MPs to rally behind the Prime Minister.

Or read the letter to her constituents from Leader of the Commons Andrea Leadsom, a passionate campaigner for Leave, who warns today that Brexit may be stopped in its tracks if the Commons votes against the deal. Indeed she says: ‘I must support the deal... to make sure we get the Brexit so many of us voted for.’

In less than two weeks, MPs on both sides of the house will hold the nation’s fate in their hands. It is not too late for them to see sanity. Or are they really prepared to sacrifice their constituents’ livelihoods on the altar of misguided ideology?