Yet, while history will be kinder to Mrs May than the current political obituaries, she led the country, through good times and bad, with dignity and won the respect of world leaders.
No one can imagine the hourly pressures that she faced – permanently on call and making decisions on national security, and other sensitive matters, that few will ever know about.
Her job, a thankless one at the best of times, was compounded by her failure to deliver Brexit – the defining mission of her 2016 leadership campaign – as she lost control of her Government and her party.
Not a natural communicator, her oratory – and inability to reach out to others – contrasts with the ebullience and optimism of her successor who must now deliver his own central pledge, notably taking Britain out of the EU by October 31, while bereft of a Commons majority.
As former Tory leader William Hague has observed, Mr Johnson was twice elected as Mayor of London on the back of a populist agenda that was both fiscally conservative – and socially liberal – and the question now is whether he can do so as Prime Minister without being held to ransom by Brexit.
Yet, while Mr Johnson’s political past will make it difficult for him to reach out to other parties, he must use his new-found status to make the effort do so. Not only did Mrs May fail to do this when she had a great chance to do so at the outset of her premiership, but Kim Leadbeater – sister of murdered MP Jo Cox – writes today about how the “toxicity” of political debate has now reached a low.
For this, Mr Johnson needs to accept his share of responsibility and lead, from this day forward, as a statesman in the best traditions of this country. In short, he must think before he speaks.
Not renowned for his attention to detail, his relaxed style of leadership mean it is even more important that, when selecting his first Cabinet, he surrounds himself with experienced Ministers who will be both loyal – and honest – with him. In turn, Mr Johnson must be willing to listen to his critics, another failing of the outgoing PM.
And then there is the North. It is paradoxical that one of Mrs May’s last acts, as Prime Minister, was to write a heartfelt letter to The Yorkshire Post acknowledging the importance of the Power Up The North campaign. Given that she was repeatedly criticised – and with good reason – for marginalisng the Northern Powerhouse agenda, she now concedes that there is “much more to do” and hopes that her successor will make it a top priority in order “to unlock the North’s vast potential”.
And after promising to have a Northern Powerhouse Minister in the Cabinet, this newspaper is encouraged that Mr Johnson intends to honour his word. For, if he is to deliver his three objectives, namely delivering Brexit, uniting Britain and defeating Jeremy Corbyn, he needs to reach out to all – including the North. After winning the backing of MPs and Tory activists, that task begins now. As Mr Johnson himself said: “The campaign is over, the work begins.”