School Strike for Climate (Credit: Wikipedia Commons)

Greta Thunberg is quickly becoming the voice of a new generation.

Nowhere was that more evident than at the U.N. on Monday, as the 16-year-old Swede delivered a passionate and scathing message to world leaders at the Climate Action Summit. “We’ll be watching you,” she said. “You all come to us young people for hope. How dare you? You have stolen my dreams and my childhood with your empty words.”

Thunberg forcefully told politicians that the younger generations want action against climate change, as it will affect their future the most. She noted that more than 30 years’ worth of scientific studies points to mass extinction if something is not done.

“You say you hear us and that you understand the urgency. But no matter how sad and angry I am, I do not want to believe that. Because if you really understood the situation and still kept on failing to act, then you would be evil. And that I refuse to believe,” Thunberg said.

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She noted that an international plan to combat climate change by cutting current emissions levels in half over the next ten years is inadequate, as it relies heavily on technology that has not been developed yet.

“You are 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,” said Thunberg.

The meaning of those words — “young people are starting to understand your betrayal” — was evident just days before, as students around the world demonstrated in massive climate protests inspired by Thunberg’s one-person strikes in Stockholm.

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In New York, sixth grader Monica Dilley from Grace Church School said she was personally inspired by Thunberg — whom she called a “really awesome person” — to march down Broadway to Battery Park with thousands of other students, chanting for climate change justice.

Another sixth grader, Ramona Bertozzi, said she decided “to strike today because I would like my grandchildren to live. I think that would be great.”

The strike included students of all ages from middle school, elementary school and high school. The young people seemed bolstered by the change Thunberg was calling for.

Katie Arons, a high school senior who has also attended women’s marches in recent years, said she wanted to take part in the climate strike because “there’s so much change to be done in the world, and we all have to take the small steps to get there.”

Similar to Thunberg, Arons didn’t mince words when asked what she would like to tell elected officials. “Listen to what we’re having to say because soon you’ll all be gone,” she said. “Not to offend anybody but we are the future generations and we do have a voice and you should listen to us. Please.”

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–Additional reporting by Victoria Flexner.