This has been the stuff of military science fiction so far:
Faced with a growing number of missile threats, the Pentagon is looking to the U.S. Army’s field artillery to shoot down those incoming threats. An innovative system called the Hyper Velocity Projectile would allow the Army’s heavy howitzers and the Navy’s deck guns to fire projectiles that can down incoming ballistic missiles.
If we can do that, eventually we'll be able to shoot down rockets and artillery shells.
Which then demands doctrine on how you fight when your major killing arm is the major defensive arm. It might be time to brush up on science fiction stories that rely on the concept that when defensive shields are operating, offensive weapons can't be used through the screen.
It won't be quite that bad since some guns could shoot at enemies while others shoot at enemy rounds inbound. But prioritizing missions will be a new task.
We demobilized a lot of artillery units as precision fires reduced the need for massed fire to get the same effect. We may need a lot more artillery to handle both precision fires and defensive shields.
