Biggest challenge? Some might disagree.
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The global impact of climate change is “the biggest challenge of all that we face right now,” Secretary of State John Kerry told an audience in Hawaii Wednesday, putting an issue he feels passionately about at the center of a speech entitled “U.S. Vision for Asia-Pacific Engagement.”

“The science is screaming at us,” he said. “Ask any kid in school. They understand what a greenhouse is, how it works, why we call it the greenhouse effect. They get it.”