James Bloodworth writes:

The left must concern itself with formulating policy which offsets the impact of immigration on the wages of domestic blue collar workers.
That doesn't mean pulling up the drawbridge on fortress Britain, but it does mean recognising that immigration impacts some more than it does others.

Here, we must distinguish between two separate issues: what to do about immigration? and: how to protect blue collar workers?

I say this for two reasons.

First, whilst there is some evidence that immigration has a small (pdf) impact on the jobs and wages of less skilled workers - many of whom are earlier cohorts of immigrants (pdf)- it's not obvious that an immigration ban would help them, even if such a thing were practical. Conventional economics - factor price equalization - tells us that if low-paid foreign workers are excluded from the UK, they will bid down UK wages via trade instead of migration.

Secondly, immigration is only one threat to the living standards of the worst off, and probably the lesser one. There's also: technical change; globalization (pdf); secular stagnation; mass unemployment and capitalist power embodied, for example, in power-biased technologies.

Singling out immigration from this list whilst neglecting the others is simply economically illiterate. I fear doing so is based upon a cognitive bias (the salience heuristic; immigrants happen to be especially visible) and the post hoc ergo propter hoc fallacy: "immigrants have arrived and now there's lots of unemployment."

In this sense, I agree with Owen. Regarding immigrants as a threat is an old "divide and rule" tactic which disguises both the fundamental weaknesses of capitalism and the fact that the main political parties - including Labour - have lost touch with the working class.

Luckily, there are some straightforward policies that would help cushion the low-paid not just against the largely mythical threat of immigration but also against genuine dangers. Policies to increase employment - including a serious jobs guarantee - would help, as would a more redistibutive tax and benefit system, including a citizens' basic income. One good point which Piketty makes is that redistribution can actually increase support for developments such as globalization and technical change by ensuring that their benefits flow to everyone, not just to the rich.

Of course, such policies don't address people's non-economic concerns about migration. But it's not obvious that people's human rights should be abridged to satisfy what are in some cases malign preferences.

Now, I don't know whether good economics makes for good politics in this case. I'd like to think so. After all, Quislings do sometimes end up getting shot.