Britain’s Home Secretary Theresa May and France’s Minister of the Interior Bernard Cazeneuve say that the only long-term solution to Europe’s migration problem is to stop so many Africans wanting to come here in the first place:

Ultimately, the long-term answer to this problem lies in reducing the number of migrants who are crossing into Europe from Africa. Many see Europe, and particularly Britain, as somewhere that offers the prospect of financial gain. This is not the case – our streets are not paved with gold. We must help African countries to develop economic and social opportunities so that people want to stay. We must work with those countries to fight illegal migration and allow people to be returned to their home countries more easily. This means a better targeting of development aid and increased investment.

All good intentions, of course, but the trouble is, ‘paved with gold’, at least in this sense, is a relative term. The gap between income levels in Africa and Europe is massive and is likely to be so for some time. And here’s the rub; as Africans get that bit richer, more of them are likely to try their luck.

That might sound counterintuitive but it makes sense when you think about it. The increase in per capita incomes in African countries, while not doing much much to close the gap with Europe, give people the extra resources they need to emigrate. As Paul Collier said, the relationship between income and propensity to migrate is like an inverted U. The poorest would like to migrate but can’t afford it, the richest can afford it but wouldn’t gain much. It is those in the middle that have both the incentive and the means.

A fascinating report from Senegal in the Wall Street Journal found that the country’s increasing prosperity is not encouraging people to stay at home, it is enabling more of them leave.

Senegal is a stable West African democracy, and Kothiary has profited from the currents of globalization transforming rural Africa’s more prosperous areas. Flat screen TVs and, increasingly, cars—mostly purchased with money wired home by villagers working in Europe—have reshaped what was once a settlement of mud huts. The wealth has plugged this isolated landscape of peanut farms and baobab trees into the global economy and won respect for the men who sent it. But it has also put European living standards on real-time display, and handed young farm hands the cash to buy a ticket out. They leave behind a proud democracy whose steady economic growth has brought American-style fast food chains, cineplexes and shopping malls to this nation of 15 million, but hasn’t kept pace with the skyrocketing aspirations of the youthful population.

The flat-screen TVs raise expectations and the computers and mobile phones give access to information about how to get to Europe.

West Africa houses several of the world’s faster-growing economies but is also sending some of the most migrants out. Deaths along the route are also high. And yet aspiring Senegal migrants are undeterred. In Facebook chats, college students swap tips on how to avoid or appease police and bandits: “Just be polite,” was the advice a friend typed to Ibrahima Sidibé, a 28-year-old at the country’s top Cheikh Anta Diop University. Students there, Mr. Sidibé included, have cashed out their scholarships to pay traffickers for a ride to Tripoli. Even their professors have traded in paychecks to journey north, joining policemen, civil servants and teachers, said Souleymane Jules Diop, the country’s minister for emigrants. “People don’t go because they have nothing, they go because they want better and more,” said Mr. Diop. “It’s aspiration.”

As Christine Mungai, for South Africa’s Mail & Guardian notes:

One of the more intriguing nuggets about the Africa emigration story is that far from fleeing poverty, migrants out of the continent are likely to be relatively well off, and are rarely from the most destitute families. Data from the UN’s World Migration Report shows that African emigration rates to the OECD countries are strongly related to GDP per capita, and to household wealth, as these migrants are more likely to have the resources to pay for transport to and resettlement expenses in the OECD countries, and are more likely to have the education and other skills required to find jobs there. The journey across the Sahara desert and over the perilous Mediterranean costs anything between $1,000 and $3,000, and often, payment is strictly in advance. Research suggests that most people want to emigrate not because they are poor, but because their reality does not match up with their aspirations and what they expect to get out of life – it’s a relative, rather than absolute, dissatisfaction.

Research by UCL’s Centre for Research and Analysis of Migration found that the probability of migration increases in line with household wealth in Asia and Sub-Saharan Africa but decreases in Latin America, reflecting that region’s greater per capita incomes.

For most of the world, the richer people are, the less likely they are to migrate. In Africa and Asia, though, a certain level of wealth makes people more likely to migrate because they have the means and access to information.

The UCL study comments:

Our findings conform remarkably to the predictions of our simple model: whereas migration probabilities decrease in Latin America (the richest region), they increase with the individual wealth index in Africa and Asia. The association between migration intentions and various dimensions of local amenities (e.g., contentment with public services, security), however, is negative for all regions. That last point is important. Security and good government makes people less likely to migrate and the lack of it makes them more likely to do so. But cheaper travel and instantly available information about the world outside means that people are able to flee oppressive regimes in greater numbers. In Syria and Iraq, for example, outbreaks of violence against Christian minorities are nothing new. Despite their troubles, the Christian populations hung on. They had nowhere else to go and few had the means to escape. In contrast, the sectarian violence of the last decade or so is likely to spell the end of Middle-Eastern Christianity. Where once people might have stayed and fought back, or died trying, they now emigrate. Communities that have existed for two thousand years look set to disappear within decades. Last year, Syria accounted for the most migrants attempting to cross the Mediterranean. So far this year, according to the Economist, most Mediterranean migrants have come from Gambia, Senegal and Somalia, which illustrates the multi-faceted nature of the migration. Some of it is political, some of it is economic but all helped along by cheaper travel and more widely available technology. Writing in IRIN last month, Christopher Horwood, of Kenya’s Regional Mixed Migration Secretariat, commented Modern mobility is also empowered and inspired by unprecedented levels of connectivity – particularly through email and social media – and the virtual proximity of a seemingly obtainable better life. Immeasurable though it may be, we cannot underestimate the force of aspirations, dreams and adventurism of many young people stuck in what they regard as politically restrictive, socioeconomic backwaters. There is evidence suggesting that migration actually increases as countries become more prosperous and educated. As the lions of the African economy flourish in what is dubbed by some as the African Renaissance, expect more migration not less, as increasing numbers of people have the resources to migrate. Eventually, there may come a time when the wealth gap between Europe and Africa is reduced to the point where people no longer feel the need to migrate. That is unlikely to happen for many years though. In the meantime, as Africa gets richer, more people will have the knowledge and the means to migrate. The streets of Europe will still be paved with gold and more people will have the wherewithal to go looking for it. As Christine Mungai said, expect more overcrowded boats.