It would be insulting and false to dub Rishi Sunak as, in Theresa May’s infamous phrase, a citizen of nowhere. Yet with a career rooted in international banking and financial networking, our prime minister is in many ways the embodiment of the globalised economic and political order that is in crisis, and may be in terminal decline. Life, it seems, has not done much to prepare Sunak for the task he faces on the world stage of plotting a path on Britain’s behalf in a multipolar world. Ukraine, nationalism, energy shortages, climate crisis, Chinese power and refugees are among the issues he must navigate, all of them refracted through Brexit and economic downturn. Sunak is not alone among western or British political leaders in having to adjust to radically changed times. But his inexperience showed in the speech he delivered this week at the lord mayor’s banquet in London’s Guildhall. The prime minister’s annual speech in the heart of the City of London is traditionally focused on foreign policy. It’s the occasion at which Winston Churchill declared in 1942 that he had not become prime minister “in order to promote the liquidation of the British empire” and where, 70 years later, David Cameron began his speech by boasting about the “global race” that Britain was winning by making financial services and arms deals with China, Russia, Brazil and the Gulf states. Sunak’s was also a foreign policy speech. Its headline moments were about China, when he said that the “so-called golden era” in Sino-UK relations was over and, more generally, in his affirmation of a foreign policy based on “robust pragmatism” rather than “grand rhetoric”. These are transformed priorities compared with Cameron’s a mere decade ago. War, shortages, climate and Brexit have reshaped Britain’s world. Foreign policy has not mattered so much in a generation. Seasoned foreign policy watchers called the speech unstartling, which is true up to a point. Sunak is not striking out in a new direction in this distanced approach to China, for instance. In reality, the golden age that Cameron famously pronounced in 2015 lasted barely a year. From May’s time onwards, responding to Xi Jinping’s authoritarianism and preoccupied with Brexit, Britain has been increasingly putting China at arm’s length. Nothing that Sunak said on Monday was in any way at odds with that. The Guildhall speech was unstartling in other respects too. Its support for Ukraine and attacks on Russia could have come from any British prime minister since at least the time of Tony Blair. Its recital of the UK’s security and trade alliances was mostly cut-and-paste stuff. Its assertions that Britain “has always looked out to the world” and that “the world often looks to Britain” were cliched, glossing over the imperial past and the international head-shaking caused by Brexit in ways which Sunak, of all UK prime ministers, might seem equipped to confront. In these respects, one might see Sunak’s speech as typifying the way that many, not least in his own party, see the man himself. Sunak is still Britain’s unknown prime minister. It is not clear what he really thinks, or whether he himself knows, as the eminently avoidable Tory split on windfarms illustrates. Is he, in short, and was the speech also, a blank sheet of paper on which others have had to inscribe the words and themes that he lacks the clarity and conviction to supply? It is tempting to say yes, and to leave it at that. There is a plausible political argument that says the Conservatives’ electoral predicament is so severe that Sunak’s smiley blandness makes him merely the least damaging front person that the wounded party can offer. In this reading, Sunak’s task is to minimise Conservative electoral losses by posing as the man who weathers the storm. In that contest, the unimaginative vanilla of his speeches and views matters less. There is, however, another reading of the speech and Sunak. To be unstartling is to be, potentially at least, reassuring. If Boris Johnson had been giving the first Guildhall speech after the invasion of Ukraine, imagine the boastfulness and bullshit it would have contained. If Liz Truss had been the speaker, imagine the needle and preening. Both would have told lies to and about Britain. In their place, a worldview that is pragmatic rather than rhetorical – or which at least claims to be those things – is surely better than the other way about. As supporting evidence, consider what Sunak said this week about Europe. On Europe, Sunak’s tone was cautiously but unmistakably positive. Relationships were “reinvigorating”. Wider post-Brexit engagement was evolving. There would be no alignment with EU law, but “instead we’ll foster respectful, mature relationships with our European neighbours on shared issues like energy and illegal migration”. All this could mean anything or nothing. It is certainly not a U-turn on the single market, freedom of movement, or the Switzerland-style agreement that was floated from deep inside the government last month. It is not so full-hearted as to provoke fanatical leavers, and it did not say enough to enthuse the majority that now regrets Brexit. But it marks a shift from either Johnson’s evasive flannel and from Truss’s Thatcher tribute act. Consider, also, what Sunak did not say about the United States. In most Guildhall speeches by most prime ministers, America looms very large. Not in Sunak’s. Here it was America’s absence that was more striking. There was no invocation of the special relationship, and no celebration of Britain and the US leading the west. There were fewer references to the US than to Australia and to the Indo-Pacific. All this reflects, but does not admit, the new uncertainty surrounding the US’s role in the world since Donald Trump’s election in 2016 – an uncertainty that may stretch well beyond 2024. British foreign policy needs to recognise that the US is in flux, that Britain is an important country and not a superpower, that its security is at risk without treaties and military alliances, that its primary arena of engagement, irrespective of its relationship with the EU, is in Europe, that it is not an Asian or Pacific power and never will be, and that its international reputation needs to be rescued from the legacies of empire and Brexit alike. Sunak may get some of this, but too much of his party is not even close to doing so. The problem with Sunak’s speech this week is not that it offered a blank sheet of paper. It is that it wrote too small a story. It was too cautious and squeamish to match the changing moment with analysis and clear priorities. British foreign policy urgently needs to make some of the hard choices that politicians flatter themselves that they are in business to provide. Martin Kettle is a Guardian columnist