Never seen this before, but I expect it's common and it's just new to me? I'm seeing lots of my antimissiles intercept their targets, but fail to kill them. I don't know why. I speculate that this is because the enemy are armoring their missiles, and I further speculate that using a larger warhead might overcome this, so I've built a new generation of antimissiles with warhead strength 2.
Am I barking up the wrong tree?