For a leader on the backfoot, offence can be the best form of defence.

For Boris Johnson, there’s no better way to try and move the conversation on from his own political woes than picking a big fight with the EU.

But when the prime minister unveils controversial legislation on the Northern Ireland Protocol that will likely unpick parts of his Brexit deal tomorrow, he’ll be squaring up to many of his own MPs as well.

Politics Hub: New legislation will ‘fix problems’ with Northern Ireland Protocol

The bill is likely to be catnip for the ERG – that’s the European Research Group of devout Tory Brexiteers.

For others, it will spark outrage.

“It’s not just the issue itself but the style of government that believes this is OK to pursue given it’s clearly not in the national interest but is about appeasing the ERG”, said one senior Tory.

Briefings notes laying out reasons to vote against the bill have already been circulating among MPs critical of the plan.

Potential rebels will have to be careful not to wander into a trap of Downing Street’s making.

In the run-up to last week’s confidence vote, Boris Johnson was keen to conflate attempts to oust him with longstanding unhappiness over Brexit.

His loyal outrider, Culture Secretary Nadine Dorries, was upfront with her accusation the vote was a “remainer plot”.

Portraying rebels as embittered europhiles is a more attractive narrative for Number 10 than fronting up to the reality that there are deep-seated concerns held by MPs from all corners of the party.

“It so clearly isn’t [about Brexit], it’s about Boris’s total unfitness to be PM and the party’s lumbering efforts to get shot of him,” said one former cabinet minister.

But turning questions about leadership into questions about Brexit moves the prime minister onto safer territory and engages him in a fight he fully relishes having.

And it’s not the only argument the government has been caught up in over the past week.

Tomorrow will see the Rwanda asylum policy back in the courtroom after a weekend when the future King was dragged into the maelstrom engulfing the controversial scheme.

A bitter tussle over rail strikes also appears on the horizon with the transport secretary already spoiling for a fight with talk of “Marxist union barons blackmailing the country”.

Meanwhile, extending Mrs Thatcher’s “right to buy” policy risks a clash with housing associations.

And elsewhere, the long-awaited food strategy will be officially unveiled tomorrow with a paring back of more divisive measures on obesity and the environment.

This is all something of a response to Tory MPs who have called for the government to adopt a more traditionally Conservative approach.

But the grand prize for many on the backbenches is tax cuts.

What’s more, it’s clear, looking at the newspapers this weekend, that as the prime minister is weakened, low-tax Tories are feeling more emboldened.

For now, immediate changes to personal taxation are being given short shrift by Downing Street and the Treasury.

But if more problems pile up for the prime minister – be it by-election losses or partygate investigations – the calls will grow louder.

At that point, picking convenient fights may not be enough to keep wavering MPs on side.