Swedish climate activist Greta Thunberg chastised world leaders Monday, Sep. 23, for failing younger generations by not taking sufficient steps to stop climate change. "You have stolen my childhood and my dreams with your empty words," Thunberg said at the United Nations Climate Action Summit in New York. "You're failing us, but young people are starting to understand your betrayal. The eyes of all future generations are upon you. And if you choose to fail us, I say we will never forgive you," she added. Thunberg traveled to the U.S. by sailboat last month so she could appear at the summit. She and other youth activists led international climate strikes on Friday in an attempt to garner awareness ahead of the UN's meeting of political and business leaders.