For five days in January, a few hundred protesters armed with slingshots in Fort Dauphin, Madagascar, blocked the road to one of the country’s largest economic assets, a $940 million mining operation run by the British-Australian company Rio Tinto. Their grievances were local: high unemployment, alleged political corruption and unsatisfactory reimbursement for relocating homes to make room for the mine. But the protest’s effects were global and relate to anyone who wants to brush their teeth, put on sunscreen or whitewash their house.