A Goodreads user asked P.J. MacNamara:

I'm not sure if this is still the case, but I heard some years ago that the USA represented HALF of the world market for all entertainment products. That's probably as good a reason as any to put American characters in your book and set some of the story in the USA. I'm not criticising you, but I suspect that this first book represents just the tip of your American Iceberg. Do you have anything to say on this subject?

P.J. MacNamara There is something in what you say, to be sure, but I'm not quite that cynical. Just as important in my thinking were the size of the US population and the fact that practically all Americans speak English. As two of my leads are English and the third is a multi-lingual Brazilian, I needed fellow English speakers for them to interact with. Every time they went to a country where English wasn't spoken I found myself summarising instead of playing out scenes. It became tiresome and predictable. In due course I settled for three power blocks, one in the UK, one in the USA and one in Japan, with a few non-affiliated persons floating around in between. The USA group self-destructed early on but I saw to it that there were a few random survivors scattered across the globe. I managed to wangle it somehow that the Japanese group mostly spoke English too, if and when they did actually speak.

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