Carol replied to me:

...

Though how the British survived being in the middle I have no idea.

I don't know the details, but I'm certain cricket is the key.

Then Annie added:

If it was Australia we were talking about, I'd actually find that more feasible.

OK, then. The England cricket team was touring Australia when the Americans and Russians wiped each other out, and the Federation citizens are descended from the players plus the Barmy Army. The Australians moved somewhere else with better weather.

Harriere