The prime minister has a duty to be candid with the British public about the scale of the global realignment caused by a volatile US presidentOne foreign policy achievement that Donald Trump prefers not to boast about is his role in helping Mark Carney win last year’s Canadian general election. The incumbent Liberal party faced crushing defeat before Mr Trump threatened to annex Canada. Mr Carney’s candidacy was buoyed up by a patriotic rally against US bullying.Perhaps because his country has also been coveted by Mr Trump, Mr Carney has given one of the most clear-sighted responses of any democratic leader to the US president’s designs on Greenland. Addressing the World Economic Forum in Davos this week, the Canadian prime minister set out the challenge for countries whose security and prosperity have depended on a global system underwritten by the US.Do you have an opinion on the issues raised in this article? If you would like to submit a response of up to 300 words by email to be considered for publication in our letters section, please