That's true, in a shooting war with a peer we haven't had much practice since Kosovo. However, neither has Russia, and while they have been putting on a show of force in Syria, that is basically them at almost max deployment and force projection capabilities. They don't have the money or manpower to fight a prolonged shooting war. John Schindler put it best, Russia is "Mexico with ICBMs". The ICBM part is what should scare us all, especially if they have a stooge in the White House.