We have one broken down conventionality-powered heavy Ice Breaker - the new conventionality-powered medium ones will not come online for years. By then, the US will have zero heavies, none of which will be nuclear. Which in effect seeds both the Arctic and Antarctic to Russia and China - because without heavies, there is no way to break the ice to create lanes for ships.
The Chinese have one or two modern heavies and are building more - all nuclear; the Russians have dozens of modern heavies nuclear and non-nuclear. Most of the Russian heavies are heavily armed. Our new ones may be.
Cedes.
According to this article, it’s a given that the Arctic ocean will soon rival the south pacific in ice. Why would we need icebreakers of any weight?