New York Times: Every day, Yasin Mohammed Aliye stakes out a spot on his small farm to chew khat leaves, a stimulant, and guard against intruders. The khat, he explains, helps to dull the hunger. We got just one day of rain each month during the rainy season, Mr. Yasin said, referring to the days from July through September. It should have been raining every other day. Now my harvest has failed. The green hills and full fields around here belie an alarming fact: This is the worst drought Ethiopia has experienced...