With the globe getting warming some geographers estimate that shipping could pass through the North Pole by mid-century. Now I do not want to waste time debating on whether or not the globe is getting warmer or note, for the sake of this post just assume that it is. This is great news for the Scandinavian nations, the US, Canada and Russia, especially for Scandinavia, this opens a new route which should be much faster than traversing the Atlantic and/or the Pacific to ferry goods across the glove.
This is also good news for the exporting nations of Asia, but less so. The Bearing strait is a natural choke point and while a future blockade wouldn't be catastrophic, it would be terribly inconvenient. The nation that would least benefit from this is China. Will China will undoubtedly use such a passage way to ferry their goods to Europe, baring an major economic change for the Europeans or the Chinese that would drastically change the economic dynamic between the two, they also know that this passage way is even less secure than the straights of Malacca. Whereas, the US has to project power across the Pacific if it wanted to close off the Malacca straight, and be dependent on allies while it did so, it does not have that problem if it wanted to close off the Bearing straight.
Long story short, assuming the current geopolitical make up of the world remains, the opening of the north pole doesn't affect the United States all that much. Some individuals would point out that the US might be able to act with less impunity due to the fact that Russia also shares access to the straight and a like of allies that have a vested interest in aiding the US dominance in the region, I have to disagree. While a lot can change in forty or so years, the Russian fleet is but a shadow of it's former self. Russian military leaders are warning of a continued drop in operational ability if ship building rates do not change. Admittedly, this could be hyperbole by military officers trying to secure a greater share of the Russian Federation's budget, but the last twenty years indicate that their warnings are not baseless. The Russians have seen a decrease in their operational ability.
The Russian Pacific fleet has no carriers, 6 surface ships, and 19 submarines and unfortunately for the Russians, the Pacific is far from their population and industrial centers. Contrast this to the United States, where the Pacific ocean is easily accessible for the United States. The U.S has the third and seventh fleets dedicated to the Pacific. The third fleet has around 5 carrier task groups, with an accompaniments of around 2 to 6 supporting warships, and the seventh fleet has one carrier strike group and around nine tasks forces that comprise of destroyers, cruisers and support vessels. The United States also has 8 submarine squadrons, comprising between 2 to 6 submarines each. Needless the say, the US can bring a lot of force to bear in the Pacific.
This shouldn't, and probably doesn't, worry the Russians too much. Russia is far more concerned with securing it's borders as it faces a demographic crisis in the future, and won't try to contend with the United States, or China, for hegemonic influence in the region. The Russians also know that the US has little interest in stirring trouble with the Russians in that part of the world. America is focused on China, and as long as the Russians do not make any trouble in the Pacific, then they know they have little to worry about; for now at least. Geopolitics is an ever changing and fluid environment, and 40 years is a long time to look out, but it doesn't hurt to do so.