Travelling between Madrid and Barcelona on a recent weekday afternoon, I wandered into the first-class section of the train. There was only one passenger, snoozing on the black leather seats – and he turned out to be the conductor, who looked up startled at the sound of an intruder.

Spain’s magnificent high-speed rail network testifies to the dramatic modernisation of the country in recent decades. But the empty trains speeding between the country’s two leading cities are evidence of a deep economic malaise. Trouble in Spain is trouble for Europe. All the euro rescues so far have been for relatively small countries: Greece, Portugal, Ireland and Cyprus. But Spain is one of Europe’s largest economies and talk of an eventual bailout is once again commonplace.

The statistics are frightening. Unemployment is about 26 per cent; youth unemployment is more than 50 per cent. The economy is forecast to contract again this year, by about 1.5 per cent. The banks have had to be bailed out – but there is a fear that if the economy keeps sliding, they will be hit by a second wave of bad debts. The government has cut spending sharply and loosened labour-market regulations. But the fiscal deficit this year remains on track to be about 6.6 per cent of gross domestic product – and the national debt is heading up to 90 per cent, often regarded as the danger level.