Tim Worstall explains why this is at the Adam Smith Institute blog:
I’m always rather puzzled by those who shout that we’ve got to bring manufacturing back to the UK. Apparently this will solve all our problems over what to do with dim Northern lads or something. Once they’re all hammering out whippet flanges then we just won’t have a problem with unemployment ever again. The problem with this idea is that modern manufacturing simply doesn’t provide many jobs. And if it were to provide mass employment it would be very badly paid employment too:
Americans working to produce traded goods and services earn, roughly, according to their productivity. If low-skill workers in America aren’t much more productive in manufacture of traded goods and services than low-skill workers in China, then they can’t earn much more than workers in China while being employed in manufacture of traded goods and services. They can earn a rich-world wage in production of non-traded goods and services, like sandwiches and haircuts, so long as there is sufficient local demand. In other words, the only way to get less-skilled Americans a good wage in a manufacturing industry is to significantly raise their skill and productivity level. If that can’t be accomplished, they can only hope to find good wages in non-traded industries. At least, that is, until wages of less-skilled workers across the developing world come much closer to converging with those in America.
Of course, that’s all about America but the same logic pertains here as well. Chinese manufacturing wages are around $6,000 a year at present. Meaning that if we had mass employment in manufacturing, as they do, then wages would need to be around that level. Or, alternatively, UK based manufacturing would have to be much more productive to support higher wages. And “more productive” is the same as saying “uses less labour”. Thus you can have few well paid jobs (in the Rolls Royces etc of this world) or you can have many badly paid jobs (Shenzen). It isn’t actually possible to mix and match between the two.