What happened in the past two weeks has highlighted the world superpower's leadership and its loss of leadership on the climate front.

First it was the release of the documentary An Inconvenient Sequel: Truth to Power on July 28. Former US vice-president Al Gore inspired the whole world in 2006 with his An Inconvenient Truth, which helped him win an Oscar, and the 2007 Nobel Peace Prize.

In the sequel, Gore continues to warn people of the dire fallout of climate change, and also offers hope from increasing global actions, such as in reaching the historic Paris climate agreement in 2015.