‘The first duty of an MP is to do what he [or she] thinks … is right and necessary for the honour and safety of Great Britain. His second duty is to his constituents, of whom he is the representative but not the delegate.”

These are the wise words of Sir Winston Churchill, ignored by the majority of our elected representatives in last week’s vote on the Brexit bill.

In his magnificent contribution to the debate – a speech of which Churchill himself would have been proud – the veteran Conservative statesman Kenneth Clarke stated that, in opposing Brexit, his conscience was clear, but “when we see what unfolds after we leave the EU, I hope the consciences of other members of parliament remain equally content”.

He did not go as far as to quote Hamlet – “thus conscience does make cowards of us all” – but I could not help thinking that, if not cowardice, the word “pusillanimity” might not have been far from his mind with regard to the position of his colleagues.

Consider: it is widely acknowledged in Westminster that the vast majority of members of both houses of parliament regard Brexit as little short of national madness. Yet only one Tory – namely Clarke himself – 52 Labour MPs and a small band of Liberals had the guts to vote against triggering article 50 of the Lisbon treaty. As Clarke says: “I have never seen anything as mad or chaotic as this.”

In another memorable observation, the Financial Times commentator Martin Wolf writes: “What sane country would sever its ties to its most important trading partners and its strategic position in its continental councils over a feeling that its own government agrees is erroneous?” The feeling being the mistaken belief that parliament has not been sovereign throughout our membership of the EU, which it has and still is, as last week’s potentially catastrophic vote reminds us.

Alas, the mistaken belief that parliament had sacrificed sovereignty to Brussels when we joined the EU was undoubtedly one of the key factors that influenced the outcome of the referendum – midsummer madness on midsummer’s eve.

It is bad enough that MPs representing constituencies that voted Leave opted to be delegates, and not representatives exercising their own judgment. Bad enough but understandable up to a point. What seems inexcusable is the way that so many MPs representing strong Remain constituencies also voted to trigger article 50.

The lame excuse propounded by Remain MPs signing up for Brexit is, essentially, that “the people have spoken, and it would be undemocratic to ignore the will of the people”. But the truth is that they are ignoring the will of half of the people on the official count and a majority of the people when you consider that only 37% of the electorate actually voted for Brexit.

The philosopher AC Grayling has pointed out in the New European that there was an “artificially restricted franchise “on 23 June for what was, in any case, supposed to be an “advisory” referendum: unlike the case with the Scottish referendum, “we know that 16-17-year-olds were denied a vote, that a large class of expatriates was denied a vote, and that EU citizens living, working and paying their taxes in the UK were denied a vote”.

Theresa May has made a Faustian pact with the devil of Ukip, under which she is evidently prepared to aggravate the already serious problems of our economy – low productivity, austerity, and pressures on the NHS, to name but three – by leaving the customs union and the single market in order to pay lip service to control of immigration.

I say lip service because there was not much sign that she was very successful in this regard when she had sovereignty over immigration during her long years as home secretary. Nor is there any convincing evidence that reducing immigration from the rest of the EU will calm the “protest voters” who were the swing element behind the narrow victory for the Leave campaign. On the contrary: making the country poorer is a funny way of going about assuaging such anger.

Moreover, not only are our overstretched hospitals vitally dependent on migrant staff in order to function at all: so are our manufacturers and services. Thus, as Jeremy Goring, one of our leading hoteliers, recently said: “We never turn away British people for jobs. It doesn’t happen. It’s a cheap headline that is simply not true. Restricting foreigners will not mean more jobs for locals.” Again, Nick Houghton, managing director of a Nottingham food manufacturing company, said: “There isn’t a pool of unemployed workers sitting there waiting for the EU workers to go back, ready and able to take up these jobs.”

That the economy has performed somewhat better than expected since the referendum is irrelevant: Brexit hasn’t happened yet. And it is all very well saying there should be another vote when the terms of departure are known, but much of the damage, in the shape of cancelled investment and diversion of economic activity to continental Europe, will already have been done.

I am told that when those two old Bullingdon Club playmates met on neutral ground after the referendum, the foreign secretary said to David Cameron: “I ****** up, didn’t I?”

Given his popularity at the time, Boris Johnson might well have swung the result the other way. As it is, after spending years trying to join the EU in order to arrest our nation’s relative economic decline, unless our rulers experience a Damascene conversion, we are all set to throw away membership of one of the world’s major markets in order to resume our relative economic decline.