Lord William Wallace writes… Brexit endgame?

This feels like the endgame for Brexit - and quite possibly for Boris Johnson. Briefings in Sunday papers on how the prime minister will refuse to resign when Parliament next votes him down - remember, he hasn't won a single vote yet - to force the Queen to dissolve Parliament and let him fight an election on the 'betrayal' of Brexit suggest that he doesn't expect the latest negotiations to succeed, and doesn't know how to evade the terms of the Benn 'Surrender' Act.

The tactical judgement of Johnson's advisers is that they can win an election on these terms, in spite of leaving themselves open to attack from the Brexit Party for being pushed into another extension.

Others have their own tactical considerations in mind. The SNP want an early election, before the embarrassing trial of Alex Salmond is due to start in the New Year; that's one reason why they've said they're willing to accept Jeremy Corbyn as a brief caretaker prime minister. Many Labour MPs rightly fear an early election, under an unpopular leader and against an effective populist; quietly, many would welcome an alternative caretaker premier who would hold things together while the Conservative Party fell apart.

It's to our advantage for the bankruptcy of the Conservative approach to Brexit to sink in to the British public - which means an election some time after October 31st, or preparation for a referendum overseen by an interim government.

Which should come first, election or referendum? Labour strategists see the attractions of a second referendum before an election, allowing them then to campaign on their domestic agenda. The problem is that it necessarily takes much longer to prepare for a referendum - agreeing the questions and the competing campaign organizations, allowing for a better-informed campaign over several months. Since this will only happen if and when the current government collapses, it will require more than a caretaker government: a 'government of national unity' which could hold together through at least 4-6 months, presenting a budget, taking unavoidable decisions, coping with unexpected crises abroad and at home. That would mean not just agreeing on the temporary head of government but negotiating a coalition agreement, and allocating Cabinet and ministerial posts among several parties and a clutch of independents. That's a different order of complexity than a 4-6 week caretaker government during an election campaign, and requires a much higher level of mutual understanding and trust. Remember, we have hard experience of coalition government.

Events may well sweep tactical preferences away. We may find ourselves in an acute constitutional crisis in three weeks' time. The gradual departure of one-nation Tories from a party that has been taken over by its radical right may speed up. We can take advantage of developments, but we cannot control them. Jo Swinson has been right to resist accepting that Jeremy Corbyn has the right to take office if Johnson is forced out; he could not assemble a Commons majority behind him either. Replacing a weak Prime Minister for whom Dominic Cummings pulls the strings with a weaker man for whom Seamas Milne pulls the strings would provide no solution for the current chaos.

So we will most probably end up with an election first, at some point over the winter. The Liberal Democrats are getting stronger month by month, winning by-elections, gaining members, at last bringing in additional funds. Working in London, I happily note that we are taken much more seriously than we used to be. A city lawyer even said to me last week that our record in the coalition qualified us for government, and that she would now be campaigning for Chuka Umunna. And I met a businessman whose name I knew from the media, at a charity concert, who told me that he had just joined our party - 'my children persuaded me'.

An election will not leave us in an easy situation. Which would you prefer: an outcome in which one party (most probably not ours) wins a bare majority of seats on a third or less of the votes, or one which creates a Parliament with 3 or 4 significant parties apart from ourselves, none of which have more than 200 seats? But the time to worry about that will be after October 31st; we have to get past the immediate crisis first.

* Lord Wallace of Saltaire is a Liberal Democrat member of the House of Lords.