‘War, boiled down to its most brutal calculation, is a business of accounting: “blood and treasure” in the horrible expression.

Cost calculations underpin warfare in terms of hard cash damage to economies and societies – what is called resilience.

Which makes the use of one of the US military’s largest non-nuclear explosive devices – the MOAB – to kill 36 jihadis in Nangarhar province, Afghanistan, somewhat baffling in military terms.

Each MOAB, or massive ordinance air blast – nicknamed the “mother of all bombs” – costs $16m (£13m) out of a total programme cost of $314m which produced about 20 of the bombs.’

Read more: MOAB attack on Isis was a baffling choice in cold-blooded terms of cost