China has rejected criticism from the United States that its policies toward North Korea had failed, suggesting on Friday that it was the Americans, not the Chinese, who were largely to blame for the North’s embrace of nuclear weapons. In a stern rebuke that reinforced tensions between the world’s leading powers days after North Korea claimed to have tested a hydrogen bomb, a Chinese official said that it was the responsibility of all countries — not just China — to persuade the North Korean government to abandon its nuclear program. Read more