CAMBRIDGE – The Greek government needs to escape from an otherwise impossible situation. It has an unmanageable level of government debt (150% of GDP, rising this year by ten percentage points), a collapsing economy (with GDP down by more than 7% this year, pushing the unemployment rate up to 16%), a chronic balance-of-payments deficit (now at 8% of GDP), and insolvent banks that are rapidly losing deposits.
The only way out is for Greece to default on its sovereign debt. When it does, it must write down the principal value of that debt by at least 50%. The current plan to reduce the present value of privately held bonds by 20% is just a first small step toward this outcome.