I found this episode to be incredibly stupid and unnecessarily over the top.
It was tragic and pushed along a theme in the show - fall of civilizations effects on children. See Carl's transformation from an ignorant innocent kid to a soldier. See Sophia innocents. See Beth's transformation. See how Liz went crazy and Mika's grip on humanity got her killed.
Then we see the helplessness of Judith and the hope she bring.
I thought it was a powerful episode and a good one!