Every move matters on Brexit
Jeremy Corbyn says "Brexit is settled". His team is adamant that if he is in Number 10, we would leave the European Union.
It's possible, in theory, that if the deal on the table didn't look too pretty they would want to keep going back to the negotiating table somehow until the offer improved.
Labour is also committed to giving Parliament a final vote on what's on offer. But, in the big picture, today the Labour leader tried to draw a line under the issue after not a little bit of Labour agony over it in the last few months.
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It's worth remembering too that over the summer, Mr Corbyn's challenger for the leadership, Owen Smith, wanted to distinguish himself from Mr Corbyn by offering, explicitly, a second referendum.
And although you are probably bored of hearing it by now, it is the case that whoever ends up in Number 10, the biggest job that they'll have in front of them is sorting out how we go about our departure from the European Union.
That's why whatever Jeremy Corbyn says about our manner of leaving the EU matters during this campaign. And that's why it matters that, despite being asked several times whether the UK will categorically leave the EU if he's in charge, he was reluctant to answer.
And his hesitancy in answering is worth noting. There are some people in the Labour Party who believe it would be crazy to give such an assurance. If the proposed EU side of the bargain is draconian, or, in this volatile world, the facts and public opinion have changed significantly, why on earth would any political party want to tie itself to a firm position either way.
On the other side, Theresa May has made it plain that even if there is no deal whatsoever on the table, we are leaving - however foolhardy her critics say that may be.
Jeremy Corbyn's aides say it's just a hypothetical scenario - that it wouldn't arise because if elected, Labour would get a good deal.
But even reluctance and hesitancy count - because in this election, particularly over Brexit, every word and every move will matter.