The problems associated with intervention in the government bond markets are even more diverse and serious, which is also why central banks should steer clear of lending to sovereigns. It is for this reason that Article 123 places strict constraints on the Eurosystem by banning the monetary financing of governments.
A look at European history shows that, whenever monetary policymakers have signalled a benign willingness to rescue a country from insolvency, this has put them at risk of neglecting their price control mandate. Monetary policy is compromised if it tries to serve two masters simultaneously.