Some of the most troubled economies are already full of it:
If building great roads and trains were the route to lasting prosperity, Greece and Spain would be booming. The past 30 years have seen a huge splurge in infrastructure spending, often funded by the EU. The Athens metro is excellent. The AVE fast-trains in Spain are a marvel. But this kind of spending has done very little to change the fundamental problems that now plague both Greece and Spain – in particular, youth unemployment. Worse, in some ways, EU funding for infrastructure has created problems. In Greece, milking the EU for subsidies became an industry in itself: and political connections were a surer route to wealth than entrepreneurial flair.
Labor market reforms are vital. But I don't see why the ECB cannot be a lender of last resort to avoid a depressive cycle.