Why May is keeping immigration target

Privately lots of Tories have said for years, six years in fact, that the chances of getting immigration down to under 100,000 were small.

And for as long as we were in the European Union, the UK government had no way of guaranteeing it would happen in any case.

The job prospects for young Spaniards, Poles, Italians, were arguably a bigger determinant for UK immigration than anything the UK government could do about European immigration at least.

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For as long as we have freedom of movement, part of the deal of being in the EU, we can't put a limit on the numbers, nor the rest of the EU put a limit on the number of Brits who could move around the EU.

It's also worth saying that immigration from the rest of the world, on its own, has also been well over the target of "tens of thousands" - and remember, that's the bit that is easier to control. You can see the numbers here, since the Tories came into government in 2010:

• Year ending Dec 2010: 77,000 (EU) 217,000 (non-EU)

• YE Dec 2011: 82,000 (EU) 204,000 (non-EU)

• YE Dec 2012: 82,000 (EU) 157,000 (non-EU)

• YE Dec 2013: 123,000 (EU) 143,000 (non-EU)

• YE Dec 2014: 174,000 (EU) 194,000 (non-EU)

• YE Dec 2015: 184,000 (EU) 189,000 (non-EU)

• YE Sep 2016: 165,000 (EU) 165,000 (non-EU)

Once we are out of the EU, controlling those numbers will in theory be easier. It will be the UK that decides how many people can come from around Europe, as they currently do with the rest of the world.

But while Theresa May has staunchly recommitted to the target she, as home secretary, missed for six years in a row, ministers have been also busy reassuring businesses they will be able to get the people they need, whether builders, bankers, or fruit pickers. If the economy needs them, they will be allowed to come.

That doesn't sound like a recipe for getting the numbers down to Theresa May's preferred level. And even though we are on our way out of the EU, there is still huge scepticism over whether the target is remotely achievable. So why keep it?

Sometimes in politics it's useful to ponder what would happen if they did the opposite.

Ditch the immigration target after the referendum when public concern about the levels was so obvious? Ditch it when the Tories want to pick up as many former UKIP voters as possible? Ditch it when Theresa May has spent years, with limited success, trying different ways of getting it down?

One source told me "it's just too ingrained". The political, if not the pragmatic, reasons for keeping it become clear pretty fast. Whether the target is suddenly achievable however is an entirely different debate.