The establishment of the “axis powers” in the 1930s paved the way for the Second World War.
Agreements signed between Germany, Italy, and Japan in 1936 united them in their expansionist interests and hatred of Western allies.
Amid Russia’s war in Ukraine, the Israel-Hamas conflict, and China’s repeated threats of invading Taiwan – some security and military analysts say we are on a similar path again and that Russia, China, Iran, and North Korea are the “new axis powers”.
The last time a similar term was used was in 2002 by former US President George W Bush, describing Iran, Iraq, and North Korea, as an “axis of evil” in the wake of 9/11.
Ahead of a new UK defence review, former defence secretary and NATO leader Lord Robertson described Russia, China, Iran, and North Korea as a “deadly quartet”.
There have also been warnings more than one of them risks triggering a third world war within the next five years.
Here Sky News looks at the risk they pose and how it could affect life in the UK.
Who were the original axis powers?
In the wake of the First World War, Nazi Germany, fascist Italy, and imperial Japan were all authoritarian regimes – ultimately geared towards military and cultural dominance in their respective regions.
Despite many differing views, the three leaders believed that uniting against the likes of the UK and the US would help them strategically.
In 1936, the Rome-Berlin Axis declaration brought together Adolf Hitler’s Germany and Benito Mussolini’s Italy. It was quickly followed by the German-Japanese Anti-Comitern Pact the same year.
Unlike NATO, which was set up after the Second World War to prevent another global conflict breaking out, the “axis” between Germany, Italy, and Japan was not a formal alliance.
They did not hold three-way summits and coordination during the war was often minimal, but their shared ideology divided world powers into those who subscribed to it and those who didn’t.
When did the ‘new axis’ form?
Although the four states have long been anti-Western, the axis-style relationship between them was “crystalised” in February 2022, according to the executive director of the Henry Jackson Society, Dr Alan Mendoza.
This happened when days before Russia’s Ukraine invasion, President Vladimir Putin visited his counterpart Xi Jinping in Beijing and declared the partnership between their countries had “no limits”.
After the invasion itself, economic sanctions imposed by the West forced Putin to turn increasingly towards China, Iran, and North Korea, who do not oppose the war in the way NATO does, Evie Aspinall, director of the British Foreign Policy Group, adds.
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Both Iran and North Korea have helped Russia with its Ukraine war effort, the former initially supplying drones, but more recently sending missiles. But signs of increasing cooperation between all four states pre-date the invasion.
In 2019 Iran started staging annual trilateral Naval exercises with Russia and China in the Arabian Sea – the most recent taking place in March.
And in 2021 it signed a 25-year cooperation agreement with China, in which Beijing pledged $400bn (£309bn) to boost Iran’s economy by developing the energy, transport, and manufacturing sectors – in exchange for discounted Iranian oil.
Also in 2021, China granted Iran access to its BeiDou navigation satellite system to aid intelligence sharing.
Two wars backed by nuclear powers
With Iran and North Korea already aiding Russia in Ukraine, the outbreak of the Israel-Hamas war in October 2023 marked a second major conflict with nuclear powers sat on the sidelines.
As well as clashes between Israel and its Lebanese proxy force Hezbollah, Iran is implicated in the conflict through its support of Hamas and the Houthi rebels in Yemen – who have been attacking Israel-linked ships in the Red Sea since last year.
When Tehran launched an unprecedented missile and drone strike on Israel in April, it forced the US and UK to come to Israel’s defence, bringing the two sides closer to all-out war than they have been in decades.
Meanwhile, Vladimir Putin has been strengthening ties with North Korea.
In June he travelled to Pyongyang for the first time in 20 years to sign a mutual defence agreement with leader Kim Jong Un.
After a series of photocalls, Mr Kim declared that as the “situation in the world changes rapidly… we intend to strengthen strategic interaction with Russia”.
Then UK defence secretary Grant Shapps said the visit showed how a “new axis of tyranny is working to undermine our freedoms”.
“The conversation around nuclear is back in a way it hasn’t been in years,” Ms Aspinall says.
‘China is the linchpin’
Putin has also continued to nurture his relationship with China this year.
In May, he and Xi pledged a “new era” of partnership between Beijing and Moscow, before declaring in July that Russia-China relations are “experiencing the best period in their history” at a summit in Kazhakstan.
And while a full-scale crisis has been narrowly avoided in the Middle East, many experts argue China’s possible invasion of Taiwan poses more of a threat.
Ms Aspinall says: “At the moment China is the least engaged in this axis because its economy isn’t doing hugely well so it’s been trying to keep its foot in economic relations with the West.
“But if Donald Trump wins the US presidency, US-China relations would deteriorate very rapidly.
“If Trump was to do something drastic, China could do something drastic – and in turn China would become more isolationist and you would see China, Russia, and Iran moving closer together. So China is the linchpin here.”
Dr Mendoza adds: “Russia is certainly the most aggressive of the powers – but China is the most powerful.”
He says with a real prospect of a second Trump White House, the US appears increasingly likely to defend Taiwan against China, with the potential for a “very large international conflict”, which could “easily spread to other countries”.
Not headed for WW3 – but there are threats to life in UK
As security experts have told Sky News previously, Ms Aspinall argues “we’re not headed for ‘World War Three’ anytime soon”.
But everyday life in the UK would feel the effects should the four powers move even closer together, she warns.
“There wouldn’t be public support for any major on-the-ground fighting in any of the current conflict scenarios,” she says.
“We wouldn’t have conscription of UK troops, not least because the way wars are fought is so different now – it’s much more ‘grey zone’. But for the average person – we’re headed towards a period in which everything feels increasingly less secure.”
The risks include more rampant inflation and energy price rises, similar to those caused by the Ukraine war and Houthi Red Sea attacks.
There is also a “significant” risk of increased cyber attacks on UK infrastructure, which could extend to election interference and China using its links to TikTok to “destabilise” Western society, Dr Mendoza warns.
And if the four powers trigger new conflicts, countries like the UK could see even higher levels of migration as people are displaced, Ms Aspinall adds.
She also says: “Things like climate change aren’t going to make any progress if a world order emerges where people aren’t willing to cooperate, because they depend on organisations like the UN.”
Overall, Dr Mendoza warns the four will try to “use their collective power to frustrate the free world’s freedom of access, movement, and supply”.
Is there anything we can do about it?
Recently departed British Army chief General Sir Patrick Sanders told The Times in a recent interview that NATO members can help prevent a potential third world war scenario by improving their defences.
Sir Keir Starmer is under pressure to increase UK defence spending from just over 2% of GDP to 2.5% but has so far refused to put an “arbitrary date” on the pledge.
Military sources have repeatedly warned of huge gaps in the British Armed Forces’ capabilities.
But beyond modernising the army, the new UK government needs to plan for any “bold stunts” Donald Trump might make if he is re-elected, such as provoking China or withdrawing the US from NATO, which would both endanger global security, Ms Aspinall says.
Dr Mendoza suggests the best way to do this comes back to defence spending.
“Taking a leadership position on this would be to say ‘we recognise the world has changed and we have to do more as a result’.
“Covering our defence bases would strengthen the alliance that way – sending the appropriate message both to the next US president and crucially to the enemies of the free world.”
Specifically, both experts agree the best way the UK can help counter the rise of the so-called “deadly quartet” is through continued support for Ukraine.
“If Putin wins, the lesson is quite clear – aggression wins and we can expect further aggression,” Dr Mendoza says.
“If he loses, the message is that if you try and break the free world we will try and break you back. So in a sense, the most pivotal place is the Ukraine-Russian border – pushing Putin back there will be the biggest safeguard against more aggression in the future.”
Ms Aspinall adds that with China’s Belt and Road programme investing in countries in the global south, the UK also needs to maintain its soft power to stop more countries moving to the other side of the axis out of loyalty to Beijing.