Extraordinarily - and this seems to demonstrate a complete disregard of the seriousness of defence at the heart of government - John Healey was only told what the offer was for additional defence funding on Monday afternoon.
I am told Number 10 then tried to rush and publish the Defence Investment Plan on Thursday.
Then a handbrake was applied by Mr Healey and his military chiefs. The (now ex) defence secretary made clear that racing to release the blueprint without a settlement that had been accepted by him and his team would be a risk for defence and for its soldiers, sailors and aviators.
You can only imagine the tone of the exchange that must have taken place - and I know that people were in the MOD until very late last night.
But John Healey firmly believes the settlement was inadequate and, if left unchallenged, would not enable the UK to keep the country safe or meet its international commitments - such as help defend Ukraine in the event of a ceasefire with Russia.
A key detail is that Mr Healey believes defence spending must be increased to 3% of GDP by 2030, up from 2.3% now. This would guarantee tens of billions of additional pounds for defence.
But - despite the stakes and the position of the defence secretary - the Prime Minister and Chancellor agreed just to inch it up to 2.68% of GDP within that time frame, after hitting a new target of 2.6% next year (which is already being inflated by lumping in the 0.1% that is spent on the intelligence agencies).
Utterly incredible.
What must our allies and our adversaries be thinking, let alone everyone in the UK armed forces and, frankly, everyone in our country?
We all rely on a secure UK to live, work, go to school, enjoy holidays, access healthcare, spend time with friends and families.
This is not a divine right. It happens because we have security - something that might not be apparent until or unless it is compromised...