World in Conflict/WMG

Bannon killed Malashenko's wife and daughter
Malashenko's wife was among the civilians whom Bannon opened fire upon during that one mission in Russia, since it's the only confirmed case of Americans killing Russian civilians in the game. Unless, of course, Mrs. Malashenko was in one of those apartment blocks that got demolished along the way.

Malashenko didn't die in Seattle
It's a bit of a neat wrap-up to say that Malashenko went to his death at Parker's hands in Seattle; he was clearly written with the intent that we would assume he's responsible for the final Soviet counter-attack against Sawyer's battalion, even with the invasion lost, and it would be a more interesting scenario if he were taken alive as a POW after his forces were annihilated.

The Soviet Union collapses not long after the invasion of America fails
Nicely bookending the alternate history, increased public awareness and unrest after a giant military failure, combined with their military both depleted and fighting on too many fronts without significant conquests to assimilate into the economy, leads to the Soviet Union dissolving either as an accelerated version of how it did in reality, or due to coup'de'etat and member secession motivated by the idea of a full-scale American counterattack.
 * Said counterattack might very well happen anyway. One could easily imagine a newly-minted General Sawyer commanding an amphibious assault on Sakhalin Island or Vladivostok.
 * Though considering the worn-out state of US forces in Europe, along with the fact that mainland China is opening up an entire new front, a counterattack on the USSR is rather optimistic and counterproductive.

Parker and Bannon are natives of Seattle
Explains why they were both in Seattle when they were on leave.
 * Would also explain why Parker goes from a decent officer capable of handling responsibility to the command equivalent of Death Incarnate needed to keep up with Sawyer's newfound drive, break through the Soviet lines, and win a decisive victory; he has as much a personal stake in saving Seattle as the Washington National Guardsmen.
 * Bannon was in Seattle because Sawyer had transferred him to a supply unit there after their mission in New York.
 * And Sawyer sent Parker there to "see his relatives". This isn't WMG, this is canon!

Bannon and every soldier of his company recieved the medal of honor
It's given out for actions which go beyond duty. What goes more beyond duty than letting a freaking nuke go off over your heads?