Perceived to be a savvy political operator on all fronts, one can only assume Theresa May knew what she was doing when she used the Tory party conference to make one of the most controversial immigration speeches in years.

“When immigration is too high, when the pace of change is too fast, it’s impossible to build a cohesive society,” the Home Secretary told conference yesterday. Immigration does not benefit the economy, she claimed (going against much of the most recent evidence), and was “not in the national interest” at current levels.

This was uncompromising stuff that strayed into uncomfortable territory. Perhaps unsurprisingly, the Scottish Government was heavily critical of speech. The Institute of Directors, normally Tory allies, also attacked it, saying such “irresponsible rhetoric” only pandered to anti-immigration sentiment.

So who was Mrs May playing to with such harsh words? Perhaps one must look to the next Tory leadership battle. The manoeuvring is under way. She probably had two audiences in mind: the 3.7 million people who voted for UKIP in this year’s general election and the Eurosceptic right wing of her own party. She will need to appeal to both to take the leadership.

Rhetoric like this may well win Mrs May votes from UKIP and more supporters on the Tory right wing.

What it will not do, however, is give the whole electorate an honest appraisal of the economic challenges facing the UK.

Research shows most recent migrants are educated and have jobs to go to within areas where there are skills shortages. Meanwhile, many economists accept that due to ageing populations Scotland and the UK will need many more migrants in future to pay for public services.

Another inarguable point concerns the EU. If the UK wishes to remain a member – and David Cameron for one believes it should – free movement will remain a fact of life. Mrs Merkel has already made clear that it is non-negotiable.

There is no doubting that immigration is a genuine concern in some parts of the country, especially those where public services are under real pressure. But rather than stoking these concerns for short-term political gain, it would surely be more cogent for the government to provide targeted funding and support in such areas. It should also be pointed out that these services often rely on migrants to keep them going.

There must, of course, be some controls on immigration. But these need to be sensitive to multiculturalism, the needs of the economy and reflect the 21st century global reality that people will move from country to country in search of the most enticing opportunities.

Mrs May isn’t the only high-profile Conservative to have ramped up the rhetoric, of course. Mr Cameron was criticised earlier this year for referring to a “swarm” of migrants.

But her speech only contributes to the view held by many that the Tories’ immigration narrative is not only nasty and ill-informed but, as has been pointed out by the business lobby, risks pitting the party against its own free market roots.

The party must beware the urge to lurch to the right on this issue - no good can come of it in the long run.