AP Photo

Until a couple of years ago, Israeli radio and TV regularly featured commercials warning that the country was "drying out." In one of the most powerful TV ad campaigns, celebrities including singer Ninet Tayeb, model Bar Refaeli and actor Moshe Ivgy highlighted the “years of drought” and the “falling level of the Kinneret.” As they spoke plaintively to camera, their features started to crack and peel — like the country — for lack of moisture. So compelling was this ad, so resonant its impact, I hadn’t actually realized it was no longer on the air. Alexander Kushnir put me straight. “We decided it simply wasn’t justified to alarm Israelis in this way any longer,” said Kushnir, who heads Israel’s Water Authority. How...