Marta's Mathoms

Good point. I grew up in a military family (U.S. Air Force) and when we watched my dad fly off to Vietnam, we had to do exactly that. We were told in no uncertain terms by the Military Liaison staff that we were not to cry, we were to act as if he was just going on a milk run and would be back that night, we were not to take mementos to remember them by, or in any way insinuate that we didn't expect them to return. We were supposed to make small talk about household or school stuff, just as if it was an ordinary event, so that his morale wouldn't be weakened and he wouldn't worry about us at home. John would definitely know that. Add in the typical British reserve, and that scene makes sense.