It's a salutary lesson we should all watch closely, particularly as we prepare to vote in a fortnight.
Berlusconi and Italy have been warned for years that the third-largest economy in Europe was saddled with too much debt. It has more than €1.8 trillion ($3.1 trillion) of government debt, which equates to about 120 per cent of GDP.
They were allowed to ignore these warnings for so long because of the soothing feel of low interest rates. The temperature of Berlusconi's water was the low interest rates on its debt. Everything seemed fine as long as those interest rates remained low, as they did for 11 years.
Sound familiar? John Key and Phil Goff are also brushing aside warnings about taking on more debt by pointing to our low interest rates.
Many homeowners and investors are doing the same.
At some stage, the bond market vigilantes will turn on us with their pitchforks and burning torches, just as they did with Greece, Portugal, Italy and Spain, unless we get our foreign debt under control and start saving more as a nation.
That means running budget surpluses and current account surpluses. Neither are remotely in prospect under the policies proposed by both sides of politics.
We don't know when the bond markets will turn. But when they do, it will be too late. We'll be too cooked to jump out of the pot.
Key and Goff should try to avoid Berlusconi's mistakes and becoming the boiled frogs of the South Pacific.