In December 2016, at an emergency session of the UN Security Council, American ambassador Samantha Power was seriously rattled. ‘Are you truly incapable of shame?’ she asked, her question directed at Russia, Iran and Syria’s Assad regime.

‘Is there literally nothing that can shame you? Is there no act of barbarism against civilians, no execution of a child that gets under your skin, that just creeps you out a little bit?’

She was talking about Aleppo, about the copious killing of civilians and the blocking of aid at the height of the siege. It was one of the last major speeches of her tenure, after three and a half years as US ambassador to the UN with the Obama administration. The clip went viral.

But Power now says there was nothing special about it – it was typical of many exchanges she had over the years with her Russian counterparts. The world’s perception was what had changed.

"The fact that it went viral actually says more about America and the rest of the world than it says about the eloquence of my statements, because I’ve made many more fiery and frankly more interesting and original statements. But the thing broke."