All of us have felt safe in the belief that, should any one of the thirty NATO countries be attacked, it would trigger an automatic response from all members, putting them at war with the attacker. However, today, for the very first time, I read in the Sunday Times that this is not the case. For Article 5 to become a reality, unanimity is required. If a single country were to demur, then it would not happen.

Now, in any situation that requires the unanimity of so many, it is next to impossible to envisage a scenario in which such a large number would agree. It is almost certain there will be one or more who will not, especially when what they are being asked to agree to is war. Some might argue that, in a real-world scenario, Article 5 is, therefore, worthless.

In the context of the war in Ukraine, there are two countries — Hungary and Bulgaria — who we know already would not agree, and there are likely to be more recalcitrants; one that springs to mind immediately is Turkey.

The alarming situation which now presents itself is that if a desperate Russia strikes out against either of the three Baltic states, or indeed Poland, which all four now see as a real possibility, then NATO will be shown to be impotent.

The only solution that stands any chance of making Article 5 mean what it says, which is almost certainly the reason why all of its members joined in the first place, is if the European Union came to the rescue. It could make it clear that any dissenting state would forfeit its place in the Union. Such a loss would be more than likely to bring any of the foot-draggers to heel.

In providing such a guarantee of its own, the Union would be protecting its own best interests since war in Europe would likely shatter what it has lovingly accomplished over the past seventy years.

As for NATO itself, it will need to look to the future—if there is to be one for it—at this impossibly high bar of unanimity and opt for a threshold of, say, 60%. Any member who will not agree to this should be invited to leave. That way, the remaining members will have what they have long, mistakenly, believed they always had: a cast-iron guarantee.