The scenes at Calais over the past few days raise the question of why Britain is the "favoured destination" for illegal/irregular entrants to the European Union. Several people asked me that on Twitter yesterday. For the Mail and Express, and indeed the Mayor of Calais, there is no doubt, it is the lure of our "generous benefit system" that makes us an "El Dorado". For more rational analysts, it is "Britain's extensive informal economy."

Except this is the wrong question. Look more closely at the Mail article:

Meanwhile, the number of migrants arriving in Italy is rising daily. So far this year, 91,000 Africans have landed at Lampedusa..or after being rescued at sea by the Italian navy. Numbers are expected to reach 100,000 by the end of August. In just 24 hours, between Wednesday and Thursday this week, 2,500 Africans, Syrians and Egyptians landed in Italy.

And how many of these 100,000 (not to mention those who come via Greece or Spain) end up in Calais? The same Mail article puts it at 1,300 (as do most of the other media reports of the last few days). So the Mail's next few sentences simply make no sense:

Like those before them, the latest arrivals are sent to immigration holding camps... Inevitably, they want to move on and exploit the EU’s open- borders policy. Britain is their favoured destination.

If Britain is their favoured destination, the question is surely not why 1,300 of the 100,000 are at Calais, but why the rest aren't? Admittedly the numbers here are not precise - I am comparing stocks and flows - and we do not know how many of those at Calais actually make it to the UK. But the asylum figures, now dominated by the nationalities highlighted by the Mail, are running at less than 2,500 a month, compared to the Mail's 2,500 a day figure. Many of those quoted or described in media stories have been at Calais for some time, attempting unsuccessfully to cross. It is clear therefore that only a relatively small proportion of those arriving in the EU illegally actually end up in Calais, or indeed in the UK at all.

As it happens, a recent paper reports some direct survey evidence - only for potential migrants from Senegal, but what is shows is revealing:

The summary statistics highlight the preferred destinations of potential illegal migrants as Spain, followed by Italy, the U.S. and France. 41% of potential illegal migrants prefer Spain, as opposed to only 18% of potential legal migrants, while 26% of potential illegal migrants prefer Italy, versus 15% in the case of potential legal migrants. Moreover, 16% of potential illegal migrants prefer the U.S. versus 31% of potential legal migrants, while 3% of potential illegal migrants prefer France, compared with 16% among potential legal migrants.

What about the UK? 6 percent of potential legal migrants would like to come here: and just 3 percent of potential illegal migrants (table 1 in the paper). Not inconsistent with the actual numbers at Calais, in fact.

What this means therefore is that those who do try to enter the UK via Calais are special. Perhaps they are particularly determined, while others who prefer the easier option of simply staying in Italy. Perhaps they are misinformed, and genuinely believe the UK hands out generous benefits and council housing willy-nilly. More likely, it is indeed a combination of the attraction of the UK's black economy - although Italy is hardly devoid of such opportunities - and, for some, family connections. But the point is that they are the exception not the rule: the vast majority of irregular entrants to the EU go, or stay, somewhere else. There is nothing particularly special about the UK, either in terms of its economy, benefit system or anything else, that makes it a "magnet" for irregular entrants.

None of this means that what's happening in Calais isn't a serious and difficult issue (I certainly don't claim I have any answers). But this Economist article gets it right. War, famine and political events in the Middle East and North Africa are leading to a surge in irregular migration to the EU as a whole; this is a European problem, not a British one.