San francisco was much farther from spain than russia, but that matters little as it was attached to spanish territory with a navy and local logistics to supply it, russia lacked both for alaska south. Now on the doctrine you mention, I doubt that is a very bright doctrine, it sounds more like a loudmouthed general who never studied the cold war. Russian navy would play a defensive role, the us has far more aircraft and attack aircraft, but russia has more air superiority fighters than america. Cyber warfare can be a game changer but not a winner by itself, it would only be effective with a combined strategy.
If you look at what the russian military has even post soviet area, they are not something we could just roll over, they still directly rival our military in strength of personel, armor and aircraft, russia also has some of the most advanced systems in the world combined with their antique crap, and their land would be one of the hardest spots on earth to invade, armies multitudes more powerful than russia in the past have failed to take them. Considering that the united states has only fought broke third world nations that have trouble keeping few ancient aircraft or tanks in service, I doubt any of the modern generals have a clue to what they think will happen.
The old cold war generals trained and worked day and night on strategies to fight the russians, the modern generals often have put no care or thought into it in a post soviet world. mattis on the other hand worked hard to convince trump not to strike russian assets in the last strike, which was wise of him, russia had assets ready not only to down aircraft, but to sink the entire coalition surface fleet near syria. Mattis got the name mad dog for a reason but he seems to be more pragmatic than others, he likes to avoid conflicts if necessary and avoid charging into battle half cocked.
