Rishi Sunak must decide how far he can support Volodymyr Zelensky in 2023

Barack Obama, when asked how his foreign policy was different from that of George W Bush, used to like to sum it up this way: “Don’t Do Stupid Shit.” That’s not a phrase that the scrupulously polite Rishi Sunak would ever dream of encouraging his staff to brief out to the press but it neatly sums up what the Prime Minister is trying to do abroad. First, turn off the bombast. Second, stop the feud with France. Third, reassure our allies we’re serious.

So far it appears to be working. Sunak, might be struggling at home but in Europe he is enjoying something of a honeymoon. From Paris to Kyiv, a range of emotions can be detected: from curiosity to relief at how his premiership has begun. Ringing up a set of Europe’s foreign-focused MPs, I was surprised by the common tone. “He’s restored a sense of calm and credibility,” said Benjamin Haddad, an ally of Emmanuel Macron in the French parliament. “The level of support from the UK to Ukraine is on the same level or even higher than it was under Boris Johnson,” said Vitaly Bezgin, a fellow lawmaker in Kyiv.

Honeymoons never last, though. Smiling and being polite is the easy part. The hard part is turning this goodwill into an advantage: actually using it to advance Britain’s values and goals. The test of that will be two crunches in the New Year: one diplomatic and the other financial — which together will add up to whether or not this is a Prime Minister who matters globally.

The first crunch coming for Sunak is the question of Northern Ireland. The bromance shoots with Macron are only going to lead somewhere if Number 10 makes a deal over Northern Ireland, where post-Brexit rows over its trading status have poisoned the relationship with the EU. Unless Sunak shows he has the authority over his party to land a deal, then European leaders will likely give up on thinking anything meaningful like a reset is worth investing in and will move into a mode of simply waiting for a new British government. That means he forget the kinds of deals and fixes with Europe that the economy needs.

The second crunch coming for Sunak is the question of military spending. Britain has made four big promises. The first is the Future Fighter project in the air. The second is modernising its nuclear deterrent. The third is the AUKUS pact with Australia and the US. And the fourth is simply meeting our commitments to Nato to defend the continent from further attack by Russia.

To put it bluntly, as it stands the UK is not going to be able to afford to do all of this spending only two per cent of GDP on defence. Worse still, on the frontlines in Eastern Ukraine, in places like Bakhmut, the trenches have for months started to resemble the First World War. And, as in our own Great Shell Crisis of 1915, both sides now realise this is a war about ammo. The side that wins the battle for procurement will decide its outcome. Russia has turned to 50-year-old weapons stocks and is dismantling kitchen appliances for microchips for its tanks. Ukraine has exhausted its own supplies and is reliant on Nato’s thinning reserves.

Alarmingly, the British Army’s own ammunition supplies, according to the Royal United Services Institute, would only last one week of this war. Actually building up the production lines, weapons factories and bristling reserves that helped Britain win the great wars it was involved in during the 20th century would push the costs of the defence budget even higher. Throughout the Cold War — when Britain actually prepared to fight a war with Moscow — that figure was always north of 4.5 per cent — and for much of it significantly so.

The real crunch for Sunak is this. Right across the public services a country that is getting poorer — especially compared to Germany and the US — is going to have to spend more to keep treading water.

With public services in unprecedented crisis and taxes already uncomfortably high for his own party, the Prime Minister is going to have to answer a set of very painful questions in 2023. Does he really believe that the international situation — from the defence of Ukraine to the security of Australia — is degenerating to such an extent that Britain must pay the price not to get weaker and break its promises? If so, is he ready to tax us more or push large sums away from schools and hospitals to achieve this?

And if not, is he happy to simply smile and wave over Britain’s accelerating decline in a frightening world?