Media audiences around the world took notice as Copenhagen police arrested hundreds of activists at the peak of the United Nations climate conference last December. The variety of nonviolent actions, from hunger strikes to large demonstrations, served as constant reminders that a concerned public expected the conference to result in dramatic action.
Although the two-week gathering may have ended in disappointment for most climate activists, it marked a historic high point for a movement that has swelled in strength and recognition in recent years. In addition to participation from government delegations, business groups, and academics, the estimated 45,000 people present included a large turnout from campaigners and the under-30 "youth delegation." Youth organizers said that their volunteers registered some 1,000 attendants, twice the participation of a year earlier.
The activist crowds were relentless: They raised their voices during negotiation sessions, press briefings, and lunch breaks; gathered in mobs to block passageways; and screamed loudly for adaptation aid, among other demands that attracted negotiators' attention. "It's very important that you're here," said Yvo de Boer, executive secretary of the UN Framework Convention on Climate Change, in an address to the youth delegation. "You're taking a very strong position, you're holding leaders responsible for their decisions, and, at the least, you're making it a lot less boring."
The activists' position, broadly, was a demand for "climate justice," including increased aid to developing countries to help them transition to low-carbon economies and adapt to damages caused by climate change. Many activists rallied around Tuvalu, a...