Second, there is the migration of the desperate and the ambitious, seeking a chance in a new place where at first they will be at the very bottom of some existing society. Some perish on the journey there, some get turned away, some always get through. Even modern countries are unable to seal their borders, whether to stop people getting out or getting in. Maybe you think North Korea achieves it, but it doesn't. In a country like that, some border guards will be bribeable and some too hungry or lazy to look very far for those intent on escape. British politicians, and increasingly British people, think they can stop people getting in. Enough poor and desperate and clever and ambitious people want to get into the UK for some of them to succeed. Some people are going to come here, whether we like it or not.
In the recent past - no more than a few centuries – migration, combined with a vast and cruel industry of people trafficking, has transformed the face of the Americas and Australasia. Its consequences are still being played out. In the very recent past - no more than a century - migration has changed the face of many European countries, of Palestine and - as a result of new migration from Mexico and Cuba - the USA. And these are only cases where everyone will know what I am talking about. There are dozens of other cultures and societies which have been transformed by migration in the recent past. If you think you can call a halt to it all, think again.