A chap who was a colleague - we worked together abroad, in Kabul, as it happens, our time there over-lapped - and who subsequently became a very good friend; professionally, - and yes, personally - we have supported one another, and would have one another's back.
He is a retired (pretty senior) military officer, and he is one of two good friends I made there (the other is a retired senior police officer) to whom the same dynamic applies.
I'm civilian, but, when you have worked in such places, only those who have also served there truly understand what it is - or was - like; the other thing is that such places remind you to take pleasure in, to relish, to take the time to savour, the small, civilised, pleasures of our own normal lives (such as being able to go to a very good coffee shop, and chat over an excellent coffee), rather than taking them for granted. There are countries where beng able to head out to meet someone for coffee is an unimaginable dream.
It is too easy to make (good) coffee at home, but there is something very civilised, and elegant and enjoyable about being able to meet someone for a coffee, - it is a wonderful use of the public or shared, space, and - while I do like my wine and beer, and love old pubs, - I must confess that I adore elegant coffee shops and what their place in the civilised world means.