Euro zone: What to make of the repeated claim that a more expansionary fiscal policy would enable a less expansionary monetary policy?

The consensus in the euro zone seems to be that a more expansionary fiscal policy would enable monetary policy to be less expansionary and reduce the costs associated with negative interest rates. But whether this claim is apposite is open to debate: To be sure, there are excess savings in the euro zone , b ut the y come from Germany and the Netherlands. Instead of being used to finance the rest of the world (in particular the United States), as is the case today, they could be used to finance more corporate (and not just public) investment in the euro zone. Indeed, the return on corporate capital is high and stable in the euro zone; If a more expansionary fiscal policy is to absorb the euro zone’s excess savings, it cannot be concentrated in Germany and the Netherlands alone, as unrealistic fiscal deficit s would then be required in both countries . B ut if fiscal policy became more expansionary in all the euro-zone countries, the resulting rise in interest rates would be very dangerous, as it would lead to a loss of fiscal solvency for several countries. So a more expansionary fiscal policy in the euro zone - not just in Germany and the Netherlands - would actually impose the continuation of very low interest rates.