The divergence or non-fulfilment of convergence expectations in the European Monetary Union leads to the situation predicted in the "optimal currency areas theory": To the migration of people from weaker regions.
After the outbreak of the crisis in 2008, the Southern European States have had to contend with a huge loss of human capital. The demographic situation in these countries is devastating. Italy has lost around 400,000 young people in the 25-35 age group in the last ten years. Spain has lost as many as 1.6 million. However, many of these had immigrated to Spain in the boom years before. Greece was hit hardest by the crisis. In the same age group, the much smaller Greece lost around 300,000 young people, mostly Greeks, according to various estimates (exact figures are not available).
These are overwhelmingly the best educated young people. Emigration will have a significant impact on, for example, the social systems or the capacity for innovation of these countries. The sustainability of the entire South of the EU is at stake.
Emigration has also political implications. The older voters, who are left behind, are usually not very interested in economic reforms and vote for those parties that promise high social benefits. Political change is therefore becoming increasingly difficult. In the long term, what Italy has been experiencing for decades is threatening: The South is ageing socially and politically and is becoming a permanent transfer recipient.
In northern Europe too, the effects are not just positive. The immigration of large groups, for example, is pushing rents up and wages down. Brexit or the Swiss referendum of 2014 "against mass immigration" were protests against a degree of immigration that was perceived as too high.
The eurozone should not become a larger version of Italy.
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