Canadian harbour guns and battleship deterrence

Would Britain have licensed heavy naval guns for Canadian harbour defence, and what threat would they answer?

Probably; 15-inch guns could discourage battleship bombardment, with smaller calibres covering lesser raiding threats.

Canada could probably have sought British licences for heavy coast-defence guns if it wanted to fortify its harbours. A battery built around 15-inch weapons would alarm the United States, but Washington could do little to prevent a British Dominion from installing them. Smaller 6-inch or 8-inch guns would handle many raiding threats. The 15-inch battery served a different purpose: preventing an enemy battleship from standing offshore and bombarding the port without a comparable reply.