Lives remain at risk, but as the crisis persists, the greater the political risks for the PM too.
Usually tragedies bring people together but the deaths in the Channel seem to have highlighted the differences between the UK and French governments
The prime minister is under pressure from many of his own MPs – who in turn are under pressure from a substantial number of their voters – to do more to stop the small boats coming to our shores.
So it was perhaps unsurprising that Boris Johnson made his letter to the French president public, portraying himself as offering potential solutions.
Downing Street insiders say they were genuinely surprised at what they regarded as a disproportionate response from France.
And they point out that it is not unknown for French ministers to use social media to criticise UK positions, or indeed to denounce the prime minister personally for “populism”.
Downing Street is emphasising that everything Mr Johnson asked for publicly in his letter – for example, joint patrols or an agreement on returning refugees – had already been asked for privately, but to no avail.
And those close to discussions with the French government say that many of the arguments that are now out in the open had persisted for some time behind closed doors.
It had been thought that the events of this week might have led to a willingness to revisit some of the more contentious issues.
The atmosphere, though, has instead turned more negative.
But while the sound of megaphone diplomacy has dominated much of the coverage today, there are quieter attempts to get the UK/French relationship on an even keel.
There is a move to try to get Home Secretary Priti Patel’s invitation to meet her French counterpart, Gérald Darmanin, reinstated.
I’m told that amid rocky relations with France over fishing and the Northern Ireland protocol, the entente between the Home Office and the French interior ministry is usually relatively cordiale.
So while she is currently not on this weekend’s guest list in France, Ms Patel did speak to Mr Darmanin this afternoon.
Home Office officials are already in France tonight to try to discuss closer co-operation.
And the UK government is still paying by instalments the £54m promised to France to help bolster patrols and surveillance on the other side of the Channel.
But Labour realises what a potentially toxic issue this is for Boris Johnson.
In his attack today, the shadow home secretary Nick Thomas-Symonds has targeted the prime minister’s vulnerabilities.
He deliberately echoed concerns of Mr Johnson’s backbenchers by accusing him of “losing control of the situation in the Channel”.
But he has also picked at another political sore.
With concerns about how Downing Street has handled some difficult issues in recent weeks, the Labour MP has accused the prime minister of “a gross error of judgment” over his diplomacy by Twitter.
It’s well known in Whitehall that Boris Johnson has been frustrated at the continuation of the migrant crisis.
His critics say he has focused too much on small boats, while not doing enough to tackle the underlying factors driving migration.
Lives remain at risk, but the longer the crisis persists, the greater the political risks for the prime minister too.