It is perhaps little wonder immigration is as politically charged an issue as it is, when you consider two things.
Firstly, as I wrote here, the numbers point to it being the stand-out UK social and demographic change of the 21st century.
And secondly, it is also one of the biggest and most transparent political failings, when you compare rhetoric to reality.
There were the projections made by Sir Tony Blair's government two decades ago that allowing unlimited migration from central and eastern Europe would tempt modest numbers of people to move here – and huge numbers turned up.
In the 2010s, the Conservatives repeatedly promised to cut net migration to the tens of thousands a year, and repeatedly failed.
The numbers then rocketed after Brexit, the very act that meant UK governments were entirely responsible for immigration policy for the first time in a generation.
Most people miss most political debates most of the time, but some are sufficiently totemic they are not just noticed but make the political weather.
The arguments over immigration are one of them – and what I have just set out tells you why.
This is the generational context within which this prime minister's promises perch.
It is a longevity of failure that senior politicians of various political persuasions privately accept – perhaps more so than any other single issue – has seeded a cynicism and a disillusion with how we are governed.
Sir Keir Starmer's language felt like an acknowledgement of that central point: here was a Labour prime minister, a former human rights lawyer, claiming "we risk becoming an island of strangers."
It is a phrase some, particularly on the left, regard as repulsive.
Others counter that it is a widely held perception which it is high time those in high office shared.
