As I did some tag wiki edits, I noticed a trend of having the American English spelling as the main tag, and sometimes there isn't a synonym created for it with the British English spelling. I was wondering if we do create tag synonyms for British English (although maybe this site may be from America)?
If that is a case, I thought of one that can use such a synonym:
localisation as a synonym of localization.
This should be done re-actively, not pro-actively. If at all.
Tags use US English spelling by default.
If it gets to the point where there are plenty of users tagging with Proper English (UK) or some other non-US version, then a tag may be helpful.
Until then there would be no need to set it up as most spelling differences occur on the second half of the word itself.
An example would be, typing out "local..." and the system will show you the only "localisation" tag there in its US spelling and the one to use for the post. So it's unlikely a user, when shown this, wouldn't just use that tag that is only different a letter or two in spelling alone.
American English, British English and at least one other, probably two. But that pertains to the content of the question, not the spelling of a tag. I really appreciate that link to Meta SO, as I never know about that!