Living in the UK, I use English spelling. I had assumed that US spellings – like color for colour, and dialog for dialogue – were changes that occurred when the bold yet illiterate pioneers left England.
I learned with a shock a few days ago, that the US spelling actually is older than modern UK English. The English had Frenchified and Latinised the original spelling, as they wished to emulate the French and Roman empires, and this change occurred after the US was colonised.
This knowledge allowed me to become aware of an assumption I had that we English are the true lineage bearers of our proud and noble language and traditions, rather than those new upstarts from across the pond who can’t even spell correctly.
Especially when you consider that I am only third generation English on any side of my family, it is a demonstration of the power and depth of our national conditioning.