The HBO TV series Game of Thrones is an international phenomenon. Described as 'The Sopranos in Middle-Earth', it makes medieval fantasy respectable for grown-ups.

It is also strangely educational. Foreign and security policy wonks, along with diplomats, spooks and soldiers, could all learn a thing or ten from it. If you don't have time for a doctorate or a decade of hard policy experience, you could do a lot worse than watch the series or read the books by George R.R. Martin. And it's hideously good, unclean fun.

Here are my ten strategic lessons from Game of Thrones:

  1. Trust no-one.
  2. Women who hold political power know how to use it.
  3. Make sure you have spies everywhere — your rivals will.
  4. Policy is not rational — all politics is court politics.
  5. In strategy, timing is everything.
  6. If you want a friend, get a dog, better still a wolf.
  7. When it comes to defence, don't put faith in a wall.
  8. Debt is decay.
  9. Keep your head.
  10. And don't get complacent — winter is coming.