In particular Cassy cited sluggish procurement processes holding back the U.K. alongside an ingrained aversion to risk and an over-reliance on a handful of major defense suppliers. 

The SDR recommended a three-month deadline for bringing the latest tech into use, in a bid to keep up with the pace of modern warfare.

Cassy, co-founder of CyLon Ventures, said the lesson was imperative across the alliance, stressing: “If we went up to 5 percent [spending on defense] tomorrow, but we’re still in our old habits, we wouldn’t be prepared for the future.”

“We within NATO — not just the U.K. but every other NATO member state — needs to change in order to spend any of that new money better.”

NATO Secretary-General Mark Rutte has called for all member countries to commit more money to their own defense, cautioning last week that Russia could be ready to use military force against NATO within five years.

But Cassy said other types of attack in the “gray zone” — such as cyber attacks and threats to critical national infrastructure — were even more immediate.

“We are already engaged daily in a struggle below that conventional threshold of war, which really does require us to invest properly in our wider defenses.”