Eleven years ago, the U.S. military installed a Shiite-majority puppet government in Baghdad. The cost of regime change in Iraq has been estimated at between $2 trillion and $6 trillion. Nearly 4,500 U.S. soldiers were killed. Tens of thousands were wounded. At least one million Iraqis died.
You could think of the U.S. invasion and occupation of Iraq as the most expensive startup of all time, a high-risk experiment, but with real human lives at stake.
More here.