May have to do the Thunder Bay leg disarmed:
(Rush-Bagot Treaty)
I think that ship may have sailed already.
news.usni.org/2018/04/02/littoral-combat-ship-uss-little-rock-leaves-montreal-three-months-trapped-ice
"A Canadian Foreign Affairs official said Ottawa has agreed to read the treaty in such a way that coast guard vessels may be mounted with guns by considering them weapons of law enforcement rather than war.
Canada reserves the right to arm its own vessels as well, the official told CBC News.
Under the reinterpretation, which both sides say honours the spirit of the original treaty, vessels may be outfitted with machine-guns of sizes up to .50-calibre. That would be big enough to bring down a helicopter and shoot through a light-armoured vehicle.
Colclough said the United States has no intention of equipping the vessels with .50-calibre machine-guns at this point.
Frederick Stonehouse, a Michigan-based historian who has written 26 books on the Great Lakes, said the Rush-Bagot treaty's references to wooden ships and cannons have long been obsolete.
However, Stonehouse said the spirit of the treaty remains both clear and respected by both sides.
"Certainly
the Great Lakes [have] not had any military vessels stationed on [them] since â gosh, really since the advent of that treaty.""
I think the key word is "stationed". Transit seems to be permitted.
