Above is one of the most powerful photos I have ever seen. The woman pictured is the wife of a U.S marine killed in Iraq. It's part of a series of pictures that won a Pulitzer prize - one of the few that deserved it. If you want to see the rest, it's here.

This really shows one important thing about warfare and loss. To a historian, it is far too easy to forget that every single loss is immeasurable against the other. The families suffering is immense, and whether the cause is just or not, we cannot forget this. As Stalin said - one death is a tragedy, and one million a statistic. But to the families, it will always be that one death.