> I had been visiting a client in northern Michigan and decided to cross the
> Mackinac Bridge and visit Sault Ste. Marie (Ontario, Canada)

The Mackinac Bridge? Uh, not. The Mackinac Bridge connects the Lower
Peninsula of Michigan (Mackinac City) and the Upper Peninsula (St. Ignace).
It's a five [count'm 5] mile long, suspension bridge.

If you really did what you claim, you crossed the International Bridge. It's
a short little thing; connecting Sault Ste. Marie, Ontario to Sault Ste. Marie,
Michigan.

Regardless; US Customs and Immigration at Sault Ste Marie are generally
unpleasant. I have never crossed there without being sent to secondary.
Last time, Officer Dimwit decided that my vanity plate (RAINSUX, on a
convertible) to be an expression of "hostile intent against the security of the
United States."

Really??? Canadian Immigration thought it was utterly hilarious!