WHEN UKRAINIAN gunners began firing Excalibur precision-guided shells early in the war they were cock-a-hoop. Ordinary shells required many rounds to hit their targets, even if you knew precisely what you were aiming at. Excalibur, guided by GPS, appeared to be a silver bullet: one shot, one strike. But in March 2023 something changed. Excalibur shells began falling out of the sky or failing to destroy their targets. And not just one: weeks went by without registering a successful hit. It was an unsettling reminder of how the electronic war in Ukraine has profoundly affected the visible one.
