I think there's an argument that everyone should be let in (I said 'perhaps') because it's unconscionable that they should be left to suffer the way they are suffering in The Jungle in Calais, or that they should be risking their lives in a way that would be considered an outrage if it were happening here on this island but is apparently not, so long as it's happening over there abroad. I don't know how else that suffering can be relieved, given that France is already doing a lot more than they are given credit for. Against that is the very obvious argument of the alleged pull factor: if we make it easy (hell, it's not remotely easy, is it, to get this far?) then more will come. I don't honestly know how much weight to give to either side of the argument, even while acknowledging there are many more sides to it than just these two.
What I am certain of is that continued conflict and climate change - which induces further conflict - will only exacerbate the exodus. We aint seen nothing yet. I'm also reasonably sure that the people trying to enter the UK are young and able - the very people most needed back home. In an ideal world we'd wave a wand and create world peace and people would move only because they wanted to, not because they had to. We're not in that world, so how do we improve the one we've got (without making everything worse)?
The BBC (I know I know) has an interesting feature on the naive question I asked Frank earlier:
Would Calais migrants really be better off in the UK?