Was this the moment David Lammy stepped up as a Starmer asset?

David Lammy is possibly the cabinet minister who has most exceeded expectations in the transition from opposition to government. The foreign office is a big brief, difficult to make sense of and yet potentially critical to two of the core missions of government: security and prosperity.

Speeches by foreign secretaries tend to lose themselves in fine-sounding abstractions – but on Thursday Lammy produced a surprisingly coherent defence of “progressive realism”.

In a world of new threats, he offered a resolute commitment to national defence and Britain’s international alliances. And he set out a bold case for pragmatic engagement with controversial trading partners, including China, in the national economic interest.

The boy from Tottenham has come a long way to the top table at King Charles Street, where his outer office is adorned with a modern portrait by Joy Labinjo of Ignatius Sancho, the former slave who became a celebrated 18th-century writer, composer and abolitionist. The painting, which pays tribute to the portrait of Sancho by Thomas Gainsborough, is a fine metaphor for Lammy’s purpose in this speech: to draw inspiration from the past to look ahead to the future.

Lammy opened his speech in the Locarno room by praising Ernest Bevin, Labour’s post-war foreign secretary and co-architect, with Clement Attlee, of Nato and the British nuclear deterrent. Lammy praised Bevin for being “both progressive and a realist”, taking “the world as it is, while working for the world we want to see”.

He went on to praise the later iteration of Labour’s pro-Nato, pro-US incarnation under Tony Blair, saying: “As I entered politics, from Kosovo to climate change, it was Tony Blair modernising Britain at home and abroad.” It is not often these days that you hear Labour politicians speaking with pride of Britain’s role in rescuing the Kosovan people from the attempted “ethnic cleansing” of Slobodan Milosevic.

The contrast with Lammy’s posturing in opposition could have been embarrassing. He voted against renewing Trident in 2015, as did Angela Rayner, but both of them have grown and learned since then.

As foreign secretary, Lammy has been as tough as any in standing with the Ukrainian people against Vladimir Putin’s aggression. On the subject of Nato, he went so far as to say: “Donald Trump and JD Vance are simply right when they say that Europe needs to do more to defend its own continent.”

He argued that it was both in our security interest and our economic interest to engage with China. Here, the contrast between the responsibility of government and the easy poses of opposition was provided not by his own past, but by the Conservative Party of the present. While he was speaking, the Conservatives called for Rachel Reeves, the chancellor, to cancel her trip to China.

They made themselves look shrill, while Lammy made the considered case for engagement with Beijing: “We have to challenge them not to throw their lot in with Putin.” And he echoed Reeves’s “pragmatic” case for a cautious trade and investment relationship with the rising economic power of the world.

Finally, Lammy took a notably Blairite line in justifying a tough policy against irregular migration. “There are those who have told me that this isn’t a progressive issue,” he said. “They are wrong. There is nothing progressive about leaving the most vulnerable exploited, or letting criminal gangs get rich and drive more crime on Britain’s streets.”

This may be just rhetoric – of course, the whole speech was “just rhetoric” – but at least it is the right rhetoric. And Lammy has also shown himself to be an adept operator in his first six months. It was he who used his contacts – including with JD Vance, the vice-president-elect – to set up the two-hour dinner with Keir Starmer and Donald Trump at Trump Tower in New York in September.

It was Lammy’s idea to appoint Peter Mandelson as ambassador to Washington: that may have backfired when Trump’s advisers reacted badly, but it was an imaginative attempt to manage relations with the new administration.

And this week Lammy secured the appointment of Olly Robbins as the top civil servant at the foreign office. Robbins, who was Blair’s private secretary long before he was Theresa May’s Brexit negotiator, is someone who could deliver Lammy’s ambition to modernise the foreign office.

The contrast with the faltering start made by several of his cabinet colleagues in this government’s first half-year is striking. I did not expect to say this, but David Lammy has been one of the more impressive ministers in Starmer’s troubled administration.