In US political speak, they’re fond of the phrase “an abundance of caution”.
It translates into a week of US Top Guns taking to the skies and taking out airborne objects that, frankly, could be anything.
The US doesn’t know – but a week of national security whiplash has been triggered by what they say they do know, that object number one was a Chinese spy balloon.
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In a Sunday night news briefing, the US Department of Defence (DoD) spoke of a heightened state of alert.
It says it has been more closely scrutinising US airspace and that radar filters have been tweaked to pick out smaller objects in the sky.
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We are told that recent objects posed no military threat and the DoD acknowledged that companies and organisations operate objects at altitude for research purposes.
So how much longer can this “shoot first” policy continue?
Clearly, it will depend on debris collection and analysis.
The first airborne object to be shot down was a suspected spy balloon (pictured) – but the following three have not yet been identified
There will come a point when the US knows what it’s dealing with and takes a considered view – in the meantime, it’s taking no chances.
Its president, certainly, isn’t entertaining risk – on the politics, at least.
The week started with Joe Biden criticised for a delay in ordering the shooting down of the Chinese spy balloon.
It ended with him taking to Twitter, talking tough on China – “we will act to protect our country” – as US forces scrambled to retrieve whatever they shot down over Lake Huron.
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With an announcement on his presidential run expected soon, the “weak on China” charge isn’t one that he can let, well, fly.
In closing Sunday’s briefing, DoD top brass opened a door – to headline writers and the rest.
When asked during that briefing if the airborne objects could be extra-terrestrials, US Air Force General Glen VanHerck replied: “I haven’t ruled out anything.”
The truth is out there, even if it’s not here yet.