During the last two minutes or so of his interview with David Letterman Tuesday night, John McCain got asked some tough questions, including one about the grotesque number of Iraqis killed or displaced because of his Bush’s War.

Letterman: 4,000 American men and women soldiers dead since we went into Iraq. Another 30,000 wounded. Untold Iraqis dead. We rarely hear that number. What would that number be? A quarter of a million? Half a million?

McCain: It’s hard to make these estimates, but it’s in the hundreds of thousands, obviously.

Estimating the number of Iraqi casualties, as horrific as that sounds, is extremely difficult to pinpoint given the chaotic nature of the country. The Iraq Body Count website puts the number at anywhere between 82,625 and 90,149. Other estimates, including one conducted by prestigious medical journal The Lancet in 2006, puts the number at around 600,000. Still others estimate as high as 1,194,935.

And of course we can’t discount the 2 million refugees.