The end of the century is 76 years away. That is a long time, and many things can happen between now and then.
Russia must be destroyed? Please! You are talking about the one nation with the most nukes in the world today. They have chemical and bio weapons I am sure way beyond anything you could imagine.
The USA will NEVER destroy Russia, unless we want to be destroyed too. That is what mutual assured destruction is. One country goes, they both go...completely, and the world with it.
Carl Sagan, who you may or may not know, thought that 10 nuclear devices going off simultaneously would result in nuclear winter. Are you familiar with the concept of nuclear winter?
There is no destroying Russia without destroying the USA. Welcome to COLD WAR 2!
Aside from maximizing the pressure wave affected area the concept of an airburst is to reduce the amount of fallout and with it, the amount of particulates ejected into the high atmosphere, those high, suspended, particulates being what led to the concept of 'nuclear winter'.
Of course, the treaty banned neutron bombs would get the job done with a minimum of damage to the infrastructure. (If we don't have them, I would surmise the Russians do.)
More likely by AD 2100, the Chinese will prove to be the next Hitler, and we will need the Russians to defeat that threat, just like double teaming the Nazis. Or they'll get into a scrap and we will have the good sense to let them pound each other and stay on the sidelines. (which is likely what the Chinese are wanting from the US and Russia while
they wait).
As to whether the Chinese have made sufficient inroads into global media to pull the latter off (hate week is a powerful thing, after all, especially in an election year) remains to be seen, but is something we should guard against.
It is a fine line to walk.
As Kipling said ...If all men count with you but none too much.
