Full Idea
When soldiers go to war, they undoubtedly assume a certain risk. They voluntarily expose themselves to a significant risk of being attacked. But this is entirely different from consenting to being attacked.
Gist of Idea
Volunteer soldiers accept the risk of attack, but they don't agree to it, or to their deaths
Source
Jeff McMahan (Killing in War [2009], 2.2.1)
Book Reference
McMahan,Jeff: 'Killing in War' [OUP 2009], p.52
A Reaction
This is his response to Walzer's thought that soldiers resemble people who volunteer for a boxing match. The sailors at Pearl Harbour obviously didn't consent to the attack, or accept the Japanese right to kill them.