Why so quiet, Keir? As a distinguished lawyer and as a man who takes the job of opposing the government seriously, one might have thought that Keir Starmer might have been all over the media when the government first briefed at the weekend that it was ready to “override” the UK-EU withdrawal agreement, which has the status of an international treaty and was passed into British law after it was endorsed in the election last December.

Now that Brandon Lewis, the Northern Ireland secretary, has actually admitted to the Commons, explicitly, that the government does indeed intend to break its own law, the leader of the opposition might have been expected to ignite. Maybe he’s saving it all up for prime minister’s questions, but it seems odd. All we’ve seen is one little soundbite of a subdued Starmer urging Johnson to “do a deal”, move on and tackle the pandemic. It’s Starmer’s least impressive performance since he became leader.

It seems odd. Or maybe not. Both Starmer and Boris Johnson are playing a tactical game here, and a tricky one. For Starmer has lots of Euro-baggage to lug around, and thus far he’s managed to avoid too many awkward questions about it. Now that Brexit has returned to prominence we may expect Johnson to make the most of Starmer’s obvious discomfiture. It can be summed up in one question, no doubt ready to be hurled across the despatch box – “well, Keir, what does your deal look like? A sell out! Monsieur Barnier’s poodle!”

There is plenty of material for Johnson to exploit, right up to polling day (if he lasts that long). Does Labour, after all this palaver, want to take us back one day into the EU? Will we have to join the euro? Will there be a referendum? Will there be two referendums? What about our rebate? Our fish? Migration? Sovereignty? Straight bananas?

Starmer has, in fact, said that he won’t campaign to rejoin the EU, but wants a better deal, which still begs some uncomfortable questions about a future reopening of whatever we end up with by the end of this year. Starmer’s second-referendum Europhile past means he can also be made to look unprincipled if he just becomes a vague Eurosceptic overnight.

Starmer can always reply to Johnson’s gibes that “I wouldn’t start from here”. It is fair enough, and self consciously breaking a solemn international treaty is an indefensible position, but it is greatly in Johnson’s interests to stir the European pot as vigourosly and for as long as possible. Starmer is more European than Corbyn was, and it may not be to his advantage if Johnson can still exploit the national trauma about Europe.

Brexit has, after all, served Johnson’s ambitions very well, and Brexit has formed the fulcrum of Britain’s never-ending culture wars, which the Conservatives usually win because England is more socially conservative than the left can accept. National unity and harmony is the last thing today’s Tories need. The 2016 Brexit referendum is how Johnson got to Number 10 and why, after the 2019 election, he has stayed there. His hard line won him the Tory membership and party leadership. He’s never had any personal political incentive to compromise. So he won’t.

In attracting more of the working-class vote than Jeremy Corbyn’s Labour Party, symbolically capturing the so-called red wall seats, Johnson wants to lay a few cultural traps for Starmer, including the BBC licence fee and law and order, but Europe is the biggest of all.

Starmer, has a more divided and bewildered party to manage. Cautious and meticulous as ever, he is taking his time about Labour’s line in Europe. He can’t disguise his pro-European instincts, and his party membership and MPs would not forgive him if he tried.