Excessive government spending is the main culprit, but there are other factors at play in the region's economic stagnation
Interesting Wall Street Journal editorial which discusses why European growth has been weak for so long-namely demographics and excessive government spending. The article mentions Germany and Sweden as two countries that are "better run", which is basically true, but the point that could have been added was that their better relative performance is mostly because they have implemented tax- and social benefits cuts.
Germany by the way is an example of how countries in the short run can compensate for the effects of a shrinking working age population by employing a higher percentage of the people in that age group. They still have room to increase the employment rate for a few more years but with a 5.5% unemployment rate there is a limit to that. Perhaps Germany should encourage some of those newly unemployed Southern Europeans to learn German and move to Germany?