If anything crystalised the strength of the “special relationship” between the UK and United States – forged during the Second World War and perhaps the most enduring international partnership in modern times – it was Tony Blair’s response to the attack on the Twin Towers in New York and the Pentagon in Washington, DC in 2001.

Everyone who is old enough remembers where they were on 11 September that year – 25 years ago on Friday – when al-Qaeda terrorists hijacked four planes and flew them into the World Trade Centre and the Pentagon. The fourth failed to reach the final target, the Capitol building in Washington, after crashing into a field.

Blair, then prime minister, made clear that the UK would stand by the US, come what may. “We the British are a people who stand by their friends in times of need, tragedy and trial, and we do so without hesitation now,” he said.

Shorts

In the aftermath of the atrocity which killed nearly 3,000 people – including 67 Britons – the two countries were drawn even closer in sorrow, as well as in military commitments which would last two decades.