The Government defeat reveals the majority in the House of Commons for a soft Brexit

The paradox is that Theresa May was strengthened by last week’s breakthrough in Brussels, so Tory rebels were emboldened, knowing that she was unlikely to fall

The Government was defeated by four votes tonight, 309 to 305

Theresa May’s defeat on an amendment to the EU Withdrawal Bill is like a flash of lightning that reveals a landscape hitherto obscured. There is a majority in the House of Commons for the softest possible Brexit, and so far the Prime Minister has managed to fend it off.

There have been about 20 votes on amendments to the Bill so far and each time the Government whips have managed to keep their troops in order. Until tonight, Kenneth Clarke, Anna Soubry and Nicky Morgan have been the only Conservative MPs to defy the party line.

Until now, the whips have been able to persuade potential rebels that defeating the Government would look bad: that it would look as if they were defying the will of the people in the referendum. If that argument didn’t work, the whips pleaded with Tory Remainers not to weaken the Prime Minister for fear that she might be replaced by Boris Johnson or another harder Brexiter.

This time, both those arguments failed. Dominic Grieve’s amendment, to give Parliament a legal guarantee of a vote on the Brexit deal, could be presented as a democratic check on the Government’s negotiations. It is true that some of its supporters want to stop Brexit altogether – Andrew Adonis, the Labour former minister, hailed tonight’s vote as the “first step towards the defeat of Brexit” – but most can say they simply want to hold Theresa May to account.

Then there was the paradox of the Prime Minister’s triumph last week in securing a breakthrough to the next stage of the Brexit talks in Brussels. By reaching a deal with Jean-Claude Juncker, the European Commission president, she strengthened her position in Britain. The Tory rebels calculated, consciously or unconsciously, that they could afford to defeat her on an important detail of the Brexit process without bringing her down.

In the end, the Government couldn’t make a strong enough case against Grieve’s amendment to scare the rebels off. Theresa May said at Prime Minister’s Questions this afternoon, to Anna Soubry, that the problem with it was that it would restrict her room for manoeuvre if the Brexit talks ran down towards the deadline of March 2019. She implied that having to hold a vote of Parliament in those circumstances might mean the talks would run out of time and Britain would leave the EU without agreement, the fabled “chaotic Brexit” used to frighten young children and Tory waverers.

But it would seem that this scare story is losing its power, because the soft Brexiters are coalescing around the view that, in that scenario, the best thing to do would be to delay the Brexit date. That was the significance of Jeremy Corbyn’s grandmother’s footstep last week towards a flexible Brexit date. And that will be the next test of the EU Withdrawal Bill. On its final day in the Commons next Wednesday, MPs will vote on whether the Brexit date, 29 March 2019, ought to be written into the Bill.

Tonight’s flash of lightning reminds us that most of the House of Commons voted in the referendum to remain in the EU. Although MPs accept the decision of the referendum, that means there is a majority in the Commons for the softest possible Brexit – that is, for leaving, but not necessarily in March 2019, and for staying in as close a relationship with the EU as possible.

The big question is whether that means accepting free movement of people or not. So far, I think there is a majority in the Commons for excluding Britain from EU free movement. But the landscape is shifting all the time. The next flash of lightning may reveal that the Labour Party has shifted towards accepting free movement and staying in the single market.

And all of this is before the EU Withdrawal Bill has even got to the House of Lords. And this Bill is the first and supposedly easiest of at least eight more Brexit bills to follow.