Facing the threat of an attack from Russia, Sir Keir Starmer has finally revealed he will “set out the path” to raise defence spending to 2.5% of national income in the spring.

But merely offering a timeframe to reveal an even-further-off-in-the-future date for when expenditure will increase to a level most analysts agree is still woefully short of what is required is hardly the most convincing display of deterrence and overwhelming strength.

What the prime minister should perhaps instead be doing is making very clear to Vladimir Putin – with new NATO-wide military exercises and the immediate hardening of UK defences – that his government is prepared for any Russian strike and the devastating cost to Moscow would be so astronomical as to make even the thought of hitting a UK target utter madness.

A failure to relay back to the Kremlin a genuinely resilient and tough message, raises the risk that the Russian president will increasingly regard Britain as vulnerable – despite the UK being a nuclear power and a member of the NATO alliance.

It should come as a surprise to no one that Mr Putin has ramped up the rhetoric against Britain and the United States in the wake of both countries allowing Ukraine to fire their missiles inside Russia in the past few days.

In a series of blunt messages, he first lowered the threshold for the use of nuclear weapons, then fired what he has described as a new kind of intermediate-range, “unstoppable” missile and finally warned that he has lots more of them, signalling that British and American military sites could be targets.

The warning clearly means UK military bases and warships, at home and overseas, are at higher risk.

Yet there is little evidence that anything is being done to ramp up protection around them or signal publicly back to Russia in a meaningful way that such a move would not be wise.

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Asked whether any changes have been made to put the UK military on a higher state of alert, a Ministry of Defence spokesperson said: “There has been no recent change to our general security posture across our bases in the UK or overseas.

“We constantly monitor the threats we face and our armed forces remain ready to protect the UK’s interests at home and abroad.”

There is also the inescapable – and well-known – fact that the UK lacks the ability to defend itself from large-scale missile attacks after decades of defence cuts.

It is a problem for all European NATO countries, but as Britain is the one that is being directly threatened by Moscow, then this absence of any kind of defensive shield should really be ringing very loud alarm bells.

The Russian leader has put his country on a war footing in the wake of his full-scale invasion of Ukraine.

Defence spending in Russia is set to rise by a quarter next year to 6.3% of GDP – the highest level since the Cold War.

UK military chiefs and the defence minister point to the cost to Russia – in terms of the number of soldiers killed and injured in Ukraine and the burden of the war on the economy – as a sign that the Kremlin is struggling.

But that is surely only regarding the data through a peacetime lens, rather than reflecting on the fact that Russia appears willing and able to absorb the cost and still keep fighting.

Unless the UK and its NATO allies wake up to the need to put their countries on some kind of war footing too, then their ability to counter Russian aggression and deter threats may be lost.