Thanks for reminding us who the real Enemy is. As we pursue our God-given right of self-defense (and defense of innocents), I pray we not be deceived into serving him.
What do you make of the ease with which the battle is won? Notice that the Snake had been conquered before it was struck; the fatal blow is an afterthought. The horse looks amused and St George, detached. Is it Irresistible Grace or is it a Culture looking in the rear view mirror?
The icon was painted centuries after Russia's geopolitical battles were done, yet the nationalistic interpretation lives today. I doubt that the nominally correct interpretation that you see, the battle with the Devil, was ever predominant.