Sam Gyimah and Jo Johnson were named six years ago by The Independent as two of the “ones to watch” in the new parliament. They rose through the ranks to minister of state level, just outside the cabinet. Now they have both returned to the back benches and endorsed our call for the people to have the final say over the terms on which we leave – or decide to stay in – the European Union.

Mr Gyimah was minister for universities, so he knows how damaging Brexit would be for our higher education sector – one of the UK’s most successful export industries. But he was also the minister responsible for space technology, and in his resignation statement he warns that the collapse of talks over the Galileo satellite navigation programme is a portent of unequal negotiations to come.

He makes the important point that the Brexit deal to be put before parliament on Tuesday, with the vote a week later, leaves the precise nature of the future trading relationship with the EU “yet to be agreed”.

He is quite right. Not only is the political declaration on the future relationship non-binding, it leaves open a range of options, from “Canada” to “Norway”. Mr Gyimah writes: “Having surrendered our voice, our vote and our veto, we will have to rely on the ‘best endeavours’ of the EU to strike a final agreement that works in our national interest.”

He says that the way the EU has cut the UK out of the Galileo project points to the way that terms would be dictated by the EU in negotiations to come.

It may be late in the day, but Mr Gyimah’s contribution is welcome, because at last the real debate is being engaged. He has moved beyond the attempt simply to refight the 2016 referendum to the specifics of the terms of our departure, and the power imbalance they set up in the next stage of what is increasingly understood would be a never-ending negotiation.

For that reason, we also welcome the contribution of Michael Gove, the environment secretary. In an article in the Daily Mail today, he offers a pragmatic leaver’s defence of the prime minister’s deal, with none of the bluster and willing away of inconvenient facts so typical of those calling for the fantasy of a “clean” Brexit.

Mr Gove makes the argument that the fall-back arrangements to keep an open border in Ireland, known as the backstop, are as hard for the EU to accept as they are for the UK. “We would have tariff-free access to their markets – without having to pay a penny,” he says, as well as being “largely free from the rule of the Commission and direct control by the European Court of Justice”.

And he warns his former comrades in the Leave campaign that leaving the EU without a deal “would cause considerable dislocation and disruption in the short term”. As a minister in charge of no-deal preparations, he has a better idea of what might be involved than some of the armchair logistics experts who wave away the problems.

Tellingly, Mr Gove says it is not “Project Fear Mark II” to warn of the costs of a no-deal Brexit: “If those who orchestrated Project Fear last time round were the boys who cried wolf, let’s not forget how that story ended. Too many false warnings meant that when the real threat came it wasn’t heeded.”