For the price of the Iraq War, we could give all the victims of the 9/11 terrorist attacks a burial and funeral on the planet Mars.
Excluding the 19 hijackers, 2,974 people died in the 9/11 attacks. Another 24 are missing and presumed dead, for a total of 2,998. Each Mars Rover has a weight of 175.4 kilograms, which is considerably more than the vast majority of humans. Assembly, test, launch, and a year of operations of each Rover cost about $425 million. So for $850 million, we could send a person's body to Mars, accompanied by their own personal Mars Rover, to dig a grave, bury the body, and broadcast funeral rites. Burying each of the 9/11 victims on Mars would then cost a total of $2.55 trillion, which is $450 billion less than Joseph Stiglitz and Linda Bilmes' estimate of $3 trillion for the total cost of the Iraq War.
Thanks to reader Andrew Lang for sending in this suggestion with calculations.