JOSÉ ANGEL FERNANDEZ VILLA led the biggest miners’ union in northern Asturias. Francisco Granados was a key minister in the Madrid region. Jordi Pujol was president of Catalonia for 23 years. The three men have one thing in common: they all allegedly hid large sums of money in secret foreign bank accounts. The accounts, unveiled during a rash of recent arrests and investigations, are the tip of an iceberg of corruption that now threatens to sink the Spanish political establishment. Until this week the prime minister, Mariano Rajoy, and other mainstream Spanish politicians were sailing blithely towards it. Now they are scrambling for the lifeboats.Mr Granados was one of 51 people arrested on charges of bribery and embezzlement on October 27th, including six sitting mayors. Most, like Mr Granados, belong to Mr Rajoy’s centre-right Popular Party (PP). But the main opposition party, the Socialists, faces corruption scandals too. So do the governing coalition in the region of Catalonia and the country’s two largest trade unions, the Unión General de Trubajadores and the Comisiones Obreras.The PP is the worst sinner. A former interior minister, Angel Acebes, is being probed for his role in a funding scandal that has already sent the party’s treasurer, Luis Bárcenas, to jail. Rodrigo Rato, a former finance minister and head of the IMF, allegedly used company credit cards to top up…