To describe a work as of "purely historical interest" is no criticism at all in my view.
The understanding of sea power and logistics is never outmoded. That some shallow readers, including the Nazis, who leaned far more on Haushofer than on the men cited, would draw unwarranted conclusions from their works is no criticism either.
Since the Mahan's times world armies have been mechanised, new branches of the military have come into existence (aviation, nukes, etc.) All these have changed the warfare drastically. This idea makes me sceptic about the Mahan's works' importance now, while, frankly speaking, I'm not aware of his works.
would draw unwarranted conclusions from their works is no criticism either.
I meant his idea on the Eastern Europe:
"Who rules East Europe commands the Heartland; Who rules the heartland commands the World Island; Who rules the World Island commands the World."
Did Germany command the Eastern Europe in WWII? Yes, until they lost the war. They also commanded all the the "Heartland" except for Britain.
Did the USSR command the Eastern Europe? Yes, for 45 years. Did it make the USSR master of the world? No.
Naval superiority is a key issue for the USA, since it's divided from the other most important parts of world by oceans, and good supply is top necessary for the military, so any US military operations outside its territory must be supplied by sea, but I cannot understand why the USA should remember purely military issues while the article is about Russia's purely economic activity.
"To describe a work as of "purely historical interest" is no criticism at all in my view."
Mahan was completely eclipsed by the theories of Blitzkreig and Defence In Depth. Of these, both create problems with logistics (is there a theorist on military logistics?), but I would argue that Defence In Depth worked best.
I would agree with your later point about naval power, but without the ability to project force inland (across a continent if necessary) it is like "the elephant wrestling the whale", as Napoleon commented on France vs. England.