The decision by the Labour party leadership to rule out a “second referendum” in the form of a simple rerun of last June’s poll was correct. That ship has, for better or for worse, sailed. But as every nautical mile is notched up, the passengers aboard SS United Kingdom are increasingly questioning not just the new skipper (the old one jumped overboard before the anchor even came up) but the iceberg she now steers us toward.

The first thing that has changed since the referendum campaign was of course the result, which the government had simply not planned for. Had David Cameron seriously contemplated a leave vote, this would surely always have been a two-stage process – with a democratic process to ratify the final deal.

The main reason this didn’t happen is because Cameron’s “Project Fear” was designed to present a choice between the status quo or setting on a dangerous, foggy heading to an unknown destination.

We understand why the Labour frontbench does not want to commit to [a second vote] now

That destination is only now beginning to appear on the horizon. It’s one in which we are likely to endure severe economic consequences for leaving the single market with no EU trade agreement, while we pursue a pumped-up free-market alternative with Donald Trump. How many leave voters envisaged that?

In our constituencies of Norwich South and York Central, thousands of jobs and livelihoods will be jeopardised by the course Theresa May and her crew seem to be setting. And after years of their own brutal cuts to the civil service, they now find themselves without the expertise needed to agree the right trade deals for Britain in the time they now have available and the new world that they face. Scientific research, finance and technology all face upheaval, instability and uncertainty outside the single market or an equivalent.

So giving the British people a chance to “seal the deal” with a vote on the final terms of the Brexit negotiations is not asking the same question twice. How can it be? We stand on the precipice of a new and vastly changed political and economic reality. If they really believe their own rhetoric, even Tory Brexiteers should welcome a chance to put their Brexit before the people and get their support.

They might say that democratic approval could be provided by parliament, or through another general election. Yet the government has determinedly prevented parliament having any meaningful say; and they have chosen now for the general election with a five-year term to follow – they have no intention of putting the terms of Brexit to the public again once they have been settled.

That’s why, in the absence of any other democratic means to make the ultimate choices the country faces, our party should be prepared to support giving the British people a chance to ratify or reject whatever deal the prime minister of the day comes back with. We understand why the Labour frontbench does not want to commit to that now. But we welcome their acknowledgement that, if circumstances changed, and there was a groundswell of public opinion in favour of the British people getting the final say, they would listen. As backbench MPs, we have heard the beginning of that groundswell among our constituents – and are prepared to lead the national debate as well.

Of course, we also believe a Labour deal with the EU would be very different from a Tory Brexit in terms of national security, jobs, workers’ rights, environmental protections and tariff-free trade at the very least. But we should not arrogantly assume the deal we secure is what the British people want – and the public may want the final say over a Labour Brexit too.

So we believe that they should be given the choice of which direction their country takes, once our alternatives can be clearly seen. Anything less will see our country hopelessly divided long into the future – something that surely no government would want.