As told to Anoosh Chakelian.

I think it’s always bad for any government when the official opposition is hopeless. It makes the government more accident prone. It makes it less careful. And I think overall, it’s bad for the national interest. The extent to which the way we go about pursuing the biggest disaster in modern British politics can be interrogated is rather limited because of what the opposition’s like.

Over the next year or two, it’s going to be increasingly important that people who are really concerned about the national interest – who think that a hard Brexit, a divorce from Europe, which is what we’re heading for – would be very bad for the national interest, are going to have to do more and more to try to shape the eventual outcome.

Apparently no deal wouldn’t be any problem, according to one or two ministers. And no deal having been thought through. It’s a complete nightmare. It isn’t very long ago we were told we would still be in the single market, in a customs union, able to do a free-trade deal with the EU, which would leave us no worse off. It’s either mendacious or it’s a consequence of supreme ignorance and folly, because that isn’t going to be what happens.

The right wing of the Conservative party have to a very considerable extent dominated not just the run-up to the referendum, but the consequences of the referendum. And they are encouraged by the tabloid press. The real policing of a hard Brexit isn’t done by the whips and the Conservative party, it's done by the tabloid editors. I think it’s [the government] led by the nose by them [tabloids].

[We’re told to] forget about the 48 per cent, and forget about the conventional ways in which we’ve sought to find some accommodation between majorities and minorities. That just is thrown overboard when you’ve got government by tabloids.

My own judgement is what we want to take back control of is the debate and our national interest, and we want to take it back from the tabloid press. In a mafia film, for saying that, you’d get your favourite pet’s head left on the coverlet when you wake up in the morning. Nowadays, you get a blistering personal attack from some hack employed at a tabloid newspaper. It’s awful and we’ve just got to stand up to it. I’m optimistic, because I think people are going to be sickened by it.

Even if the Labour party doesn't get its act together, I very much hope that enough Conservatives will speak up for the national interest, not for a dogmatic, Trumpian view of where this country's going, with most of our friends thinking we're completely crazy. Do you remember that, I'm not a particular football fan, but do you remember that Millwall football supporters' song? "No one loves us, we don't care." That's going to turn into our position in the world.

The negotiations [will] turn out to be at best incredibly difficult, and at worse a pretty good disaster. Don't forget, we've been told that this is all going to be wonderful, and that because the Italians like selling us prosecco, everybody will fall over to give us whatever trade terms we need. I mean, that is the depth of the geopolitical wisdom of the Foreign Secretary and others. It's beyond depressing.

Events will shape the debate, and events will eventually oblige Conservatives, including the Prime Minister, to make a choice between national interest and bloody-minded dogmatism.

Chris Patten is a peer and former Conservative party chair. He is Chancellor of the University of Oxford, and was chairman of the BBC from 2011-14.