Be worried, be very worried, if Trump backs out of NATO
By the Rt Hon. Jim Murphy, Founder and Executive Chair of Arden Strategies
“I don’t care about defence so it doesn’t worry me that President Trump might back off from NATO.”
This is what I was told by someone in my network this week.
It was in response to more frenzied media reporting that the US President was considering diluting America’s NATO commitments.
For those who don’t follow defence politics here’s some background and two reasons why the US leaving NATO matters (a lot):
The Background
NATO is a voluntary alliance of 32 nations who have come together to collectively protect themselves and one another from war. Clement Attlee’s Labour government ensured that the UK was a founding member back in 1948.
Congress would prevent President Trump from taking the US fully out of NATO. Congress, ironically encouraged by the current Secretary of State Marco Rubio, now requires a super-majority for a NATO withdrawal. President Trump doesn’t have the votes to take the US out of NATO. But a President can consciously uncouple the US from its most important NATO responsibility which is its Article 5 commitments. This is what Alexandre Dumas would have described in his 1844 book as “All for one and one for all”. This unity is what makes NATO so effective. In plain terms, if any NATO nation is attacked all other NATO countries have a Treaty commitment to come to their aid.
A weaker NATO makes war more likely
At some point in its history France has been at war with every other NATO member, except Iceland. Germany (a much younger country) has fought against more than two thirds of NATO members. But in the 75 years since NATO’s formation no member nation, including France and Germany, has been at war with another NATO member. It is an organisation that has helped confound all historical trends.
Only one NATO country has ever invoked Article 5: the US after 9/11. No other nation has ever needed to because all potential adversaries know that an attack on one will lead to an unequal and opposite reaction from the thirty-one others.
But Russia would see a weaker NATO as a strategic opportunity. Putin launched his full-scale invasion of Ukraine partly because as a non-NATO member it wasn’t protected by Article 5. In 2022 there were smaller, easier countries to invade in the region. While Ukraine has a lower per capita income than any NATO nation, it is bigger than all but three NATO members; its population is greater than all but five NATO members; it had a mid-tier defence budget with pre-war armed forces larger than 19 NATO members.
Defence is about deterrence. A weaker NATO denudes its institutional disincentive against an attack by outsiders against one of the UK’s fellow NATO members. And on the basis that the UK would undoubtedly remain committed to Article 5, we would be Treaty bound to come to the aid of a NATO ally in their hour of need. A failure to do so would destroy NATO.
Therefore, a NATO with only 31 nations committed to collective defence makes the chances of war far greater.
The NHS needs Trump to stay committed to NATO
If Trump reneges on Article 5, Europe and Canada will have to invest in becoming more of an independent credible threat to external aggressors or lose the deterrence affect. This would require huge investment that would be painful to fund across multiple countries simultaneously. The aggregate consequence of a continent prioritising defence investment at a pace ahead of all other spending plans would have significant political consequences in every NATO member state – and may destabilise some governments.
A far milder version of this is already at play after Trump (rightly) demanded that other NATO members carry more of the cost burden of collective defence.
But if the US reneged on Article 5, the other 31 members would have to configure their forces in a way that gave confidence that an attack on one wouldn’t mean a defeat for all. The US budget is twice as large as all other NATO members combined and is impossible and unnecessary to replicate. But a non-US NATO would have to fill some of the capabilities that only the US can currently commit to collective defence.
That’s a long list but for illustrative purposes would include stealth aircraft, amphibious landing at scale, a strategic bomber force, and satellite infrastructure. We would also want to fill the gap that is the 70,000 expensively equipped US personnel currently stationed in European NATO nations. A US no longer committed to Article 5 may mean that in the event of an attack, these forces wouldn’t leave their bases to come to Europe’s defence.
The ultimate US deterrent against Russian aggression in Europe has long been the US nuclear umbrella which signals to Moscow ‘If you nuke Europe or Canada, we will nuke you’. This Mutually Assured Destruction is understandably controversial. But unprotected by that US insurance policy, the UK and others would have a choice – accept that their collective nuclear capability may not be perceived as a credible deterrent by Russia or invest in a larger, shared, and terrifyingly expensive capability – centred around the UK and France.
All this costs. On current trajectories the defence budget is due to grow at a faster rate than the health budget in the years to 2035. And the trajectory for defence spending was set on the assumption that the US commitment to NATO and Article 5 was guaranteed.
I am not advocating for any policy but simply reflecting the conversation that will become unavoidable in such a state of geopolitical shock. And none of these choices are free. UK taxes can’t go up much further; the bond market will baulk at unfunded new defence promises. Instead, if Trump departs from Article 5 there will be an argument about whether we have to take investment out of the things we love (the NHS) for something that we need (defence).
There are of course other consequences of a weaker NATO: curtailed freedom of the seas (not ideal for an island nation such as ours); lower economic growth from geopolitical uncertainty; a potentially emboldened China on Taiwan (if the US won’t come to Europe’s aid, would they protect Taiwan?).
For months I have been saying to clients that if Keir Starmer (alongside Finland’s Trump-whispering President, Alexander Stubb) manages to keep President Trump attached to Article 5 then both Starmer and Stubb should go down in history as genuinely consequential leaders.
Finally, every time I see Keir Starmer deliberately not respond to the latest Trump provocation, I am one of the few that is relieved. I know that others would rather Starmer mimicked Hugh Grant’s character in Love Actually who publicly confronts the fictional US President.
But keeping President Trump and his successor committed to NATO’s Article 5 is the strategic play. And for this, the PM and the country need strategic patience and a thick skin.
Hopefully we (and the NHS) never need to find out just how expensive it would be for the UK and others to fill the gap created by a US absenting itself from Article 5.
