Washington | When Donald Trump jnr, the President’s son and an avid fisherman and sports hunter, agrees with actress Jane Fonda about the environmental threats posed by an Alaskan copper project once part-owned by Rio Tinto, it catches the eye.

Mr Trump’s son, who normally spends his days trying to “trigger” America’s left on social media, stunned environmentalists by issuing a full-throated call recently for his father to block the Pebble Bay mine that sits atop the pristine headwaters of Bristol Bay, the world’s largest salmon run.