Army Chaplain, the human dimension of the soldier, and suicide

[Schmedlap]

... does this suspicion have an empirical basis beyond instinct?

The hypothesis is derived from instinct. I'm not sure if empirical analysis would confirm it.

Did cohesion at the squad and platoon level develop along commonalities of age and marital situation? If so, did the shared experience of combat mitigate this over time?

My impression is that cohesion developed along commonalities in garrison. Once deployed and the small unit members were watching one another's backs and relying upon one another on tactical missions and living 3 feet from one another when back at the patrol base, then the commonalities became less important - perhaps unimportant. Once the unit redeployed, the cohesion primarily shifted back to age/marital status. Again, just my impression.