World War One began with the killing of one man, Archduke Franz FerdinandThe heir to the throne of Austria-Hungary. He was assassinated in Sarajevo in June 1914 aged 50, which led to the start of World War One. of Austria. Four years later, 20 million people had joined him in the grave.¹

So it is no surprise fears rose of a repeat when HamasA militant Palestinian organisation, which has controlled the Gaza Strip since 2007. It is listed as a terrorist organisation in the UK. leader Ismail Haniyeh was assassinated by what is believed to be an Israeli bomb last week.

The killing of Haniyeh was a humiliation for IranA country in Western Asia, officially called the Islamic Republic of Iran. It has a population of 84 million. . Many believe they will respond with their own attack on IsraelA country in the Middle East, and the only Jewish nation in the modern period. It is seen by Jews, Christians and Muslims as the Holy Land..

Then, the story goes, the two powers head into all-out war. The USA intervenes on Israel's behalf and Russia backs Iran. China takes advantage of the chaos to attack TaiwanAn island country in east Asia. China still claims to be the legitimate owner of Taiwan, while the Taiwanese government until recently claimed to be the legitimate government of the whole of China. and the USA finds itself fighting on three fronts. World War Three has broken out.

But will it happen? Experts are unsure. People have been predicting World War Three for decades. We came close during the Cuban Missile CrisisA confrontation between the US and the Soviet Union that occurred after the USSR installed missiles on the island of Cuba, within 140km of Florida. in 1962, and still survived.

And conditions are less dire today. Although we tend to think Europe "sleepwalked" into World War One, it began because many European powers believed they could win a short war, release the tension, and reset the balance of power in their favour.²

This is not true in the Middle East, where war is in no-one's interests. Iran knows all-out war with Israel would further shatter its economy and mean being dragged into lethal conflict with the all-powerful USA.

It would also be a disaster for Israel. The high-skilled workers in its tech sector would likely flee a regional war, crashing its economy.³

And war with Iran would mean fending off attacks from all directions: the HouthisAn Islamist rebel group that controls a large part of Yemen. They are allies of Hamas in Gaza. in the south, Iraqi militiasA militia is an informal armed group operating independently of the state. to the east, and, most of all, HezbollahA militant organisation based in Lebanon, classified in the UK as a terrorist group. It has made direct attacks on Israel and is believed to have been responsible for assassinating Lebanon's former Prime Minister Rafic Hariri. to the north, over the border in Lebanon.

Hezbollah commands at least 50,000 soldiers and as many as 200,000 missiles, enough to overwhelm Israel's Iron DomeIsrael's air defence system to protect itself from missiles. It uses radar to detect rockets and fires missiles back to intercept them. missile defence.⁴

It does not want to use them. It has become increasingly unpopular in Lebanon and the Lebanese people will not thank them if they impose a new war on their battered country.⁵ But if Iran and Israel go to war it will have no choice.

Little wonder the countries involved are looking for an off-ramp. Iran reportedly offered not to strike Israel if it accepts a ceasefireAn end to fighting - often temporary. in GazaThe smaller of two Palestinian territories, home to two million people. It is located on the Mediterranean coast, bordered by Israel and Egypt. , which it turned down.⁶

The most probable outcome, experts say, is that Iran finely tunes a response that is just below the threshold for Israel to declare war, and we go on as before.

Even if war did break out in the Middle East, they argue, it is not likely to escalate. The USA has shown in Ukraine that it will not risk direct confrontation with Russia and resulting nuclear war.

World wars come about, they argue, when large blocs with few economic and political ties between them face off. In 1914, that was the competing empires of Britain, France, Germany and Russia. During the Cold WarA period of diplomatic conflict between blocs led by the USA and the USSR that lasted from 1947 until 1991, when the USSR collapsed., the East and West were completely separate. That meant they lost nothing by going to war.

Today the great powers are interlinked by trade. War would destroy all their economies. They will go out of their way to avoid it.

Are we panicking?

Yes: The world is no longer set up for war. It has a single, interconnected economy in which conflict in one area can devastate the whole. Nuclear weapons deter any escalation between great powers.

No: The Middle East is stuck in a deadly game of deterrence. Each party knows a display of weakness could invite more attacks, but showing too much strength could trigger war. We could end up in an accidental conflict.

Or... There will probably be no world war, but regional wars are breaking out all over the globe. It is easy to forget that much of humanity is not benefiting from the current "peace".

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