I’m in an airport bar in Houston, Texas, and I’m falling apart. Three hours ago I was in a rented apartment researching a story I was working on. But now, suddenly, unthinkably, I’m on my way to South Africa, and I need a drink, urgently.

When the barman hands me my glass of Shiraz I fumble and drop it. It shatters on the floor, and everyone looks at me.

“I’m sorry,” I tell the barman him as he mops up the red stain. “My son just died.”

Back behind the bar, he pours me another glass.

“He’s calle...