Opportunity Costs of the Iraq War

Some of you have seen or heard my musings on this issue before. This Quora answer seems to have gotten some traction, so I reproduced it here:

What could America have bought and built for itself with the trillions of dollars spent in Iraq and Afghanistan over the last decade?
Nobel laureate economist Joseph Stiglitz places our war costs over $5T. A NY Times infographic (http://www.nytimes.com/interacti...) puts the tally at $3.3T. Leaving aside the politics of whether our money has been wasted, what could it have bought, had it been spent at home?

$3.3 trillion is a lot of $$.

For example it is equivalent to:

$60,000 for the poorest 50% of Households. (about 57,000,000 households)

End the Eurozone crisis by paying off Greece, Italy, Spain, Portugal and Ireland's national debt. (Together, their national debt's are just over $3 tril)

Endow over 100 new Harvard Universities (Harvard's endowment is $32 bil)

Guarantee Unemployment below 5% for the next 6 years, offering $40,000 a year to volunteer for charity. (13million unemployed, 9% of country)

About 150 Manhattan Projects (each costing about $24billion)