Inter Press Service: Growing U.S. support for U.N. initiatives is raising hopes among those who want to see the world community take immediate and concrete action to tackle climate change, although their optimism is also tinged with scepticism. "So far, the response by the world’s governments has been less than sufficient," said U.N. Secretary General-Ban Ki-moon at a news conference held outside the world body’s headquarters in an open space filled with leafy trees. In pushing the U.N. agenda on …