Within 48 hours of the 7/7 bombings in London in 2005, in which four suicide bombers killed 52 innocent people on their way to work, we were already getting intelligence details of the brutal attack.
They were leaks, and they came not from British security sources, but from American ones.
I was in London at the time, and was busy investigating every angle we could uncover about the attackers: who they were, where they had come from, how they had built their bombs.
The information helping us build that picture was coming from Washington and New York.
And we were not alone. An American news network received pictures of unused bombs, apparently recovered from the bombers’ vehicle, which had been dumped at Luton station, just north of London.
The police refused to confirm or deny these “extra” bombs existed.
Traditionally Britain’s intelligence services have been very tight-lipped about any information they have. Very few journalists ever develop sources within their ranks, and they are to a very high degree walled off from even the chance of divulging their secrets.
On issues of national security, Britain’s police too set a high threshold on the details they will reveal. The intention behind this caution is to give them every chance to round up accomplices, keeping the element of tactical surprise on their side.
In 2005 the police didn’t publicly express their outrage that their “cousins” in American intelligence had given away vital details about the investigation.
To this day it has never been publicly acknowledged the additional bombs existed – or what they might have been intended for.
The speed and volume of intelligence leaks this time around, in the Manchester investigation, feels faster and greater than following the 2005 attack.
This difference is an indication of both the scale and the interdependence of counter-terrorism operations in the post-ISIS era.
ISIS has drawn far more recruits from far more countries far more quickly than al Qaeda ever managed, and that is putting intelligence agencies at the mercy of each other’s integrity more than ever before.
British intelligence services were quick to contact their American allies to try to figure out bomber Salman Abedi’s recent travels, the answers to their queries came back quickly, and that – of course – is vital to British investigators trying to figure out if another attack is imminent.
Speedy reliance on one’s allies, and being able to share information in situations like this is not an option – it is a necessity.
A necessity which no doubt fuels the frustration and anger Manchester’s police and UK Home Secretary Amber Rudd are feeling: they want to save lives, and they don’t want to feel their efforts are being compromised.
But they are not the first to feel let down – it has happened before.