On Jan. 29, the leaders of France, Italy, Spain, Portugal, Greece, Malta and Cyprus will meet for this year's EuroMed 7 summit, where they’ll discuss immigration, Brexit and eurozone reform, among other issues. On the surface, many of these Southern European countries share similar perspectives on EU policy, such as supporting increased spending measures and risk-sharing within the bloc. However, a combination of internal economic weakness, political disagreement and diplomatic frictions will hinder the region's ability to present a united front to Brussels....