(2/n)
...Treaty of Mastricht, which created European Monetary Union, thus ensuring that the Deutsche Mark would not appreciate all to much for its exports' prices to become uncompetitive.
After reunification, with Germany suddenly being 1/3 larger than any other EU country, that imbalance has become bigger and bigger, as the East was brought up to Western standards.
Such an imbalance is unhealthy in matrimony, and it is, too, in international relations.
Two Germanies...