Leading article: Mr Duncan Smith takes a wrong turn

Increasingly, it seems, ministers are using speeches abroad to air views that might prove controversial, or harmful to Coalition unity, at home.

Thus the Chancellor can be heard defending the euro more often in Brussels than in London. The Deputy Prime Minister advocated handing out shares in Britain's rescued banks while on a visit to Brazil – an idea almost instantly ruled out by the Treasury. And now the Work and Pensions Secretary, Iain Duncan Smith, has given a speech in Madrid in which he called on firms to recruit Britons rather than relying on migrants.

Leaving aside the echoes of Gordon Brown's scandalously chauvinistic "British jobs for British workers", which was joyously seized upon by the BNP, Mr Duncan Smith has a clear position to defend. Architect of one of the most comprehensive overhauls of the benefits system ever, he will judge its success by how many of the unemployed get jobs. And it can be argued that the willingness of well-educated migrants to take low-paid, low-skill work must reduce the pool of jobs open to unskilled or low-skilled Britons. Last year, Mr Duncan Smith said, almost half of all newly filled jobs went to foreign nationals.

In asking employers to give British workers a break, however, Mr Duncan Smith is not only suggesting something that could be illegal, but trying to tackle a defect of the country's labour market from the wrong end. Migrants are not the problem; poor skills and lack of training among young Britons are. So, in some cases, may be the value of state benefits compared to the low pay so many unskilled jobs command.

As Work and Pensions Secretary, Mr Duncan Smith is on the right track in trying to increase incentives for British people to work. But he is on quite the wrong track in suggesting that employers should prefer British workers. Such a stance would be immoral; it could be illegal, and without competitive home-grown workers to be recruited, it would not have the desired effect.