The Nato summit was not the electoral gift that Boris Johnson would have wished for

International occasions have been a boon for previous leaders, but in this case acrimony was the order of the day

Sometimes Boris Johnson’s unusual representations of the truth – what are sometimes impolitely termed “lies” – hide in plain sight, so to speak.

His years as a journalist have endowed him with the capacity for the most brazen, floridly outrageous statements, and he has developed a rare capacity to deliver them with a straight face and without a hint of blushing.

So after the most acrimonious Nato summit anyone can recall, insults flying and deep strategic differences openly on display, Mr Johnson confirmed the alliance to be “rock solid”, its soon-to-be-30 member states sheltering beneath its “giant shield of solidarity”.

If only. What Theresa May planned earlier in the year as a full summit and celebration of its 70th birthday, hosted by post-Brexit “global Britain”, turned into a backbiting mess, downgraded to a short meeting with no communique.

The Turks argued with the French, the Americans argued with everyone, the British were ignored and the president of the United States called the prime minister of Canada “two-faced”. Short of them chucking bread rolls around at the banquet, it could hardly have been worse. There was more attention paid to a supposed huddle of Trump-sceptics, possibly including Princess Anne, at a Buckingham Palace reception than there was to the small matter of keeping the west safe. Peeved by Emmanuel Macron and Justin Trudeau, President Trump departed the Watford non-summit prematurely, abandoning his press conference. On balance, this was probably a positive outcome for the British prime minister.

In the past, British premiers have found international trips and summits during election campaigns a useful boost to their appeal. There they are, the voters are invited to reflect, with President Eisenhower or General Secretary Gorbachev or Chancellor Merkel, strutting the world stage, respected as equals, their prestige enhanced. Gordon Brown was so desperate to be seen with Barack Obama that he walked through the kitchens at the UN with him. Very unusually, Mr Johnson made every effort to avoid being seen with President Trump, and went to the trouble, it would appear, of asking the president to rule out taking over the NHS, as a pre-emptive move. The only problem with this strategy is that it relies on the British electorate taking the word of Mr Trump at face value.

It doesn’t, and the worries about drug prices under a UK-US trade deal persist. Although it seems unlikely to swing many votes now, Labour’s continuing pressure on public services and the non-Brexit agenda is a sensible one. John McDonnell, one of Labour’s few leading figures with their wits about them (the Tories suffer a parallel front-bench talent deficit), promised to “abolish poverty once and for all”, no less. It seems churlish to quibble, but it is difficult to identify many examples in human history where such a state has been achieved.

To help it along, Mr McDonnell had the bright idea doing a reverse costing exercise on his manifesto. Thus the question is not how much households might have to pay for the Labour programme in more taxes, but putting a monetary figure on the impact of the national living wage, lower energy bills, rail fares, free broadband and the like to families – £6,700 or so per year.

Like the so-called four-day working week (for five days pay), and funding the £580bn bill for justice for the Waspi women, the problem here is that the voters are sceptical. If they were not doubtful about any of this being real, then presumably Labour would now be enjoying a 20-point lead over the Tories and an imminent landslide victory. Who wouldn’t vote for such a socialist paradise, fully costed by the shadow chancellor in his “grey book”?

But people seem more inclined to go by the old adage that if an offer looks to good to be true, then it probably is. The Tories have been more careful about their promises, both lavish and vague as some of them are. Perhaps it is simply a question of choosing the devil you know. At any rate, in international diplomacy as in the election campaign, the prime minister is still getting away with it. Unlike his predecessor, he seems to have a little more luck on his side.