The Herald has argued consistently that a one-size-fits-all policy does not work for immigration when the conditions and requirements of the south-east of England bear no relation to those in central Scotland.

The unfortunate, unintended consequences of such a policy are well illustrated by the case of Andrew Wilbur. Dr Wilbur is precisely the sort of immigrant for whom Scotland should be throwing down the red carpet. Though born in California, he has lived in Scotland for the past 14 years and has had a Scottish wife since 2006. The holder of a doctorate in human geography from Glasgow University, he has received a glowing testimonial from his head of department. He has proved himself already to be an adept teacher of undergraduates and should have been looking forward to a successful academic career. But Dr Wilbur will be on a plane out of Scotland next week, after falling foul of new immigration rules.

These state that his household income had to exceed the arbitrary figure of £18,600 in the past year. The rule came into force only two months ago. As he was studying for his doctorate and his wife's employment was interrupted by family illness, they were not able to meet this criterion and Dr Wilbur has been told by Border Agency officials that he must leave. They now face the prospect of being obliged to live apart, at least for a time. Though in their early 30s, they have been forced back on the hospitality of their respective parents.

These rules are not only unfair on Dr Wilbur and his wife. They are not in the interests of a country like Scotland that desperately needs talented migrants to study and settle here. At the most basic level, they are tomorrow's taxpayers. That was the rationale behind the Fresh Talent initiative, introduced by the last Labour-LibDem administration in Scotland under Jack McConnell. This aimed to persuade 8000 students over five years to stay on after graduation and seek their fortune in this country.

What has changed in the interim is the election of a Conservative-led Coalition that came to power on the back of a pledge to crack down on non-EU immigration. There were certainly issues that needed to be confronted. The Herald's reports exposed the situation regarding bogus students visas. And there are communities, mainly in the south of England, where the infrastructure and public services have struggled to deal with a rapid influx of migrants. Scotland, where barely 2% of the population are first-generation immigrants, is in an entirely different position. Dr Wilbur is the hapless victim of a rash, monolithic, ideologically-driven diktat that ordained that non-EU immigration would be reduced to "tens of thousands" by 2015. It is a classic example of using a sledgehammer to crack a nut. It sends out the wrong message from a country that should be writing Welcome on its mat.