Why immigrants are the key to our prosperity

Swamped. Full. Bursting at the seams. That's the predominant view of Britain from abroad. The expatriates I encountered on a recent trip to Kenya barely mentioned the wars in Iraq or Afghanistan or melting polar ice-caps, but there was one topic everyone asked about: UK immigration. "From what I've heard, I won't recognise the place," fretted one, as if the dome of St Paul's had been covered by a giant burqa and Glen Almond was now a fully-functioning madrassa. And all of them tossed around that emotive language that suggested it was time for Fortress GB to pull up the drawbridge and erect large billboards around the coast declaring: "Sorry, we're full."