British political attention during next week’s Nato summit will focus laser-like on Donald Trump. This would have been so even if Britain were not in the midst of an election campaign. But the proximity of the election means the spotlight on the rightly unpopular US president’s visit from Monday to Wednesday will be even more searching than at a less sensitive time. The hope – or fear – that Mr Trump will lob a last-minute firework into the campaign is palpable among the competing political parties this weekend. Journalists will be lining up next week to offer him a blue touch paper to light.

Labour and the other opposition parties confess privately that they would be thrilled if Mr Trump said anything to confirm their allegations this week that health services and the prices of drugs would be integral to any bilateral post-Brexit trade deal. Were this to happen, Labour’s struggling campaign might suddenly become jet-propelled. If Mr Trump could at the same time be provoked into a fulsome endorsement of Boris Johnson or a denunciation of Jeremy Corbyn as a threat to everything the president holds dear, then even better.

Normally, these would be good enough reasons to assume that Mr Trump will do no such thing. But you never know with this president. Conservative party strategists have long been aware that the Nato summit, and Mr Trump’s presence at it, provide a potentially dangerous moment for them. They are certain to have been working overtime to persuade the White House that the president should stick closely to his hosts’ preferred script. The Tories will want Mr Trump to keep his election endorsements suitably statesmanlike and low key or, even better, to wrongfoot Labour by making unexpected assurances on the NHS.

Amid what is certain to be a febrile campaigning context next week, the danger is that the Nato summit itself will be largely overlooked. This would be both unfortunate and ironic. It would be unfortunate because the substantive issues facing the partners are difficult, urgent and in need of resolution. But it would be ironic because there has been no UK general election in which Britain’s place in the world was more at stake than this, nor one in which foreign policy has played less of a role in the campaign.

Britain has a longer and larger record of commitment to Nato than any of the 28 allies, with the exception of the US, who will gather outside Watford for the summit on Wednesday. But Nato now faces the uncertain commitment of Mr Trump to the alliance. This was exemplified most recently by Washington’s withdrawal from northern Syria to permit Turkey, also a Nato member, to invade. But uncertainty about the US’s thinking predates the volatile Mr Trump. His immediate predecessors, George Bush and Barack Obama, were also impatient with the alliance, particularly over burden-sharing.

Britain’s response has concentrated on keeping the show on the road. But President Macron of France has rightly been more challenging. He has attacked Nato’s response over Syria as “brain-dead”, and suggested that “new alliances and new ways to cooperate” against the threat from terrorism, including in the Sahel, will be needed. This in turn has triggered a flurry of alarmed exchanges with Nato’s eastern European members, who see Russia rather than terrorism as the main threat.

All these issues will come together next week. But it is not clear that they will be resolved in anything approaching a decisive way. The summit is expected to establish a “group of experts” to work on Mr Macron’s complaints. Meanwhile, although overall defence spending in Nato has risen, figures this week show that expenditure by 19 of the 28 allies remains below the 2%-of-GDP pledge agreed in 2014.

Logically, Britain ought to be working with France to lead and redefine Nato’s role from the European side. But Brexit, far from meaning that Britain will “do more on the international stage” as the Tory manifesto claims, means the reverse. If the claim were true, all eyes next week would be on whether Nato’s difficult issues were being purposefully resolved. Because it is false, all eyes will simply be on Mr Trump and his impact on Britain’s domestic arguments.