You ARE from Michigan, right? Maybe you'd better contact Mackinac County officials and tell them they've been spelling it wrong for over 100 years.
Go to:
http://www.mackinaccounty.net/
It was spelled Michilmackinac in 1818, and then shortened to Mackinac in 1837. I've got family records of my ancestors that were voyagers coming through that area in the late 1700s and still called it something close to Mackinac.
There is no "Mackinaw" county that I've ever come across. Where are you getting this from?
Mackinaw city yes, county no. island, no. bridge, no.
You can call something whatever you want, but many things have official names - including the bridges and counties in question.
As to using English, as mentioned previously . . . few Americans speak the Queen's English. We speak American English which is quite different, and has many words with silent letters, many words that were once pronounced wrong, and/or spelled wrong, or any combination of errors concievable - and are now correct after years of useage. That's also a big difference between American English - and French when it comes to rules of change. The French language is policed for accuracy and prohibits most change.
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