My point is this.
A ground war is decided by the combination of technological advances in weaponry and the amount of firepower you can field.
And while the US Military is a technological marvel. The Russian military is on par with it in most areas. Now in terms of armour (Yes I spell it with a U), Russia has about 20,000 Main Battle Tanks whereas the US has about 9,000 M1's. Russia has a large navy, it may not be as powerful as the US Navy but each side is almost certain to be crippled beyond operational standards. Russia's troops are just as well trained as US troops and are fully equipped with modern firearms.
And the air war is a stalemate. Both sides have 4.5 and 5th generation aircraft in substantial quantity and both sides have high quality anti air weapons.
If you ask any US military strategist they will say the same thing. If you read the book "Plan of Attack" by Dale Brown and "The sum of all fears" by Tom Clancy. It demonstrates how much of a threat Russia is.
The fact we are having this argumet proves the point. America's only direct competition is from the Eastern Bloc which is China and Russia. And both nations have huge militaries with modern equipment and recently Vlad Putin is increasing military spending.
Also geographical location is a serious issue. The US is seperated from the main continent, While Russia has direct access to NATO and the Middle East, Oil and Food. What a combo. Whereas the US would have to field an entire military across the ocean to get its full brunt into battle. WHile I do not doubt NATO's strength. To ask NATO to stand in Russias way would be like asking a mouse to fight with a cat.
All this taken into account proves only one sequence. Russia starts a fight somewhere and deploys its MASSIVE ground force, the Russian Airforce with overwhelming numbers and effective modern aircraft achieve complete air superiority. the US Joins in and restores the balance, but in this kind of war it will become attrition warfare and Russia will evenmtually gain the upper hand. The Coalition is forced to use nuclear supression. GTNW. End of world.
At least, that is the result of every scenario put forward for WW3.