After the end of the Cold War, it was believed that the 21st century would be an era of peace and prosperity. However, even the most optimistic were in for a surprise as there was an emergence of new geopolitical conflicts that have claimed thousands of people’s lives worldwide. From the civil wars in the Middle East to ethnic tensions that have destroyed some parts of Africa, the past two decades have seen quite a few horrendously lethal wars. Here are the Top 10 Deadliest Wars Of The 21st Century, curated by the Top 10s Only team.
List Of The Top 10 Deadliest Wars Of The 21st Century
Despite its technological advancements, the 21st century has been marred by numerous conflicts. These wars have claimed countless lives, displaced millions, and left lasting scars on nations. Here’s a look at the top ten major wars of the 21st century.
1. Afghanistan War (2001 – 2021)
The Afghanistan War is among the worst conflicts of the 21st century. The war started as a military intervention by the United States in Afghanistan to oust Al Qaeda, the mastermind behind the September 11 terrorist attacks of 2001. The Taliban regime had provided refuge to Al Qaeda and its head, Osama Bin Laden, in Afghanistan, and the USA wanted to flush them out. The initial campaign to topple the Taliban was successful, and many believed that this would be a short-lived conflict. However, this went on to become one of the longest wars in the 21st century. Supported by Pakistani counterparts, Al Qaeda, and other terrorist groups, the Taliban continued the insurgency and terrorism and this had a catastrophic impact on Afghanistan. As per reliable sources, more than 1 lakh people have been killed since 2001, and over 4 million displaced. The Taliban and other militant groups are accused of many human rights abuses, including the recruitment of child soldiers. In 2018, the U.S. and the Taliban signed a peace treaty to end the conflict. The Afghanistan War ended in 2021 with the re-establishment of the Islamic Emirate of Afghanistan.
2. Land Cruiser War Or Darfur Conflict (2003 – 2020)
The War in Darfur, also called the Land Cruiser War, was a major conflict in Sudan’s Darfur region. The conflict began in February 2003 when the JEM (Justice and Equality Movement) and SLM (Sudan Liberation Movement) rebel groups fought against the Sudanese Government for oppression of the non-Arab population of Darfur. This led to a brutal crackdown by Sudanese President Omar al-Bashir, who was supported by Janjaweed (Arab militia). Janjaweed committed terrorism and ethnic cleansing against the Darfur population, resulting in the deaths of at least 3 lakh people and the displacement of three million or more. Only by 2008, to some extent, peace was restored by the African and UN peacekeeping forces. In 2009, the International Criminal Court issued a warrant against President Bashir for the first time, seeking the arrest of a head of state that showed the atrocities committed by him in Darfur. In 2010, the JEM and the Sudanese government signed a ceasefire agreement for peace only to be disrupted by sporadic violence. After many retaliations and negotiations, on August 31, 2020, a comprehensive peace agreement was signed to end armed hostilities. This was truly one of the worst wars of the 21st century.
3. Iraqi Conflict (2003 – 2017)
The Iraqi War, also called the Second Persian Gulf War, is one of the deadliest wars in the 21st century. It began in March 2003 and lasted until 2017. The conflict was between the Iraqi government of Saddam Hussein and the U.S.-led coalition. The main cause of the conflict was the invasion of Iraq by the United States to dethrone Saddam Hussain from power and disarm weapons of mass destruction. The war was one of its kind as sophisticated weapons, including cruise missiles, chemical weapons, etc., were used. Apart from the damage to buildings and infrastructure, the death toll stood at 275,000–306,000 killed and 9.2 million displaced. The cost of the war is estimated to be more than $3 trillion, making it one of the most expensive wars in recent times. Plus, it had a great impact on the stability and security of the region.
4. Boko Haram Insurgency (2009 – Present)
Among the list of the 10 deadliest wars of the 21st century, the Boko Haram Insurgency is one of the most brutal and prolonged conflicts. This horrendous conflict started in July 2009 when the militant Islamic group Boko Haram launched attacks against the Nigerian government to impose Islamic Law or Sharia in the country. The group based in North-East Nigeria is said to have ties with extremist organizations like Al Qaeda and has become a great threat to not just the stability of Nigeria but the entire West Africa. After deadly raids on police in 2009 by Boko Haram, the government responded with a military operation, which angered the group and led to a full-blown insurgency. Over the years, Boko Haram has launched attacks on civilians and the military and targeted schools and churches. They have killed and kidnapped hundreds and thousands of people and have drawn international condemnation. The conflict at one point escalated to such an extent that troops from Niger, Cameroon, Chad, and Benin had to be deployed. At the peak of the insurgency, Boko Haram was one of the deadliest terrorist organisations and the violence has claimed about 350,000 with 35,000 direct deaths and displaced 2 million or more people. The conflict against Boko Haram is considered an international problem, and the U.N. has been helping find a resolution. While international organisations and the government have been partially successful in containing Boko Haram, it still is a great threat to the region’s stability.
5. Syrian Civil War (2011 – Present)
The Syrian Civil War, which started in 2011, is among the worst wars in the 21st century. It is a complex conflict that is multi-layered and is due to a combination of external as well as internal factors. The Civil War is being fought between the Syrian government and various Jihadi groups and the Free Syrian Army and began as a protest against President Bashar Al-Assad’s regime. The Arab Springs protest in 2011 calling for political reforms spread nationwide, with the Syrian government responding with a violent crackdown. The uprising turned into a war, with the government using military forces to suppress the people, which resulted in a civil war. The war has been violent, with the government accused of war crimes and also for using chemical weapons and even targeting hospitals and medical personnel. The war has become a humanitarian crisis, with more than 5 lakh people dead and millions displaced.
Most political analysts agree that the war could not have reached this magnitude without external help. There has been great foreign involvement with Saudi Arabia, Turkey, Iran, Russia, and the United States involved with regional factions. These countries have supported different sides, providing political support, arms, and money. While it is not clear if foreign involvement has led to this immense destruction, its consequences are felt throughout the country. The only way a resolution can be had is via a political settlement.
6. Yemen Civil War (2014-Present)
The Yemen Civil War is an ongoing conflict that began in 2015 between the Yemeni government led by President Abdrabbuh Mansour Hadi and a Zaidi Shia-led group called Houthi. The war began when Houthi, a religious-political group, began an uprising, claiming they were the rightful leaders of Yemen. In response, the President, who had the backing of Saudi Arabia and the United States, launched a military offensive. This escalated to a civil war, with many sides fighting to gain control over the country. The war is one of the deadliest in the modern world, with more than 3 lakh direct and indirect deaths and many more displaced due to it. The conflict has resulted in a major humanitarian crisis, with more than 17 million needing medical and food aid. The lack of access to these has resulted in the cholera outbreak, enhancing the suffering. The warring parties are currently committed to a ceasefire brokered by the UN.
7. Russo-Ukrainian War (2014 – Present)
The ongoing Russia-Ukrainian War started in February 2014 after Russia occupied Crimea from Ukraine and also supported separatists who were fighting with the Ukrainian military. In 2022, after eight years of conflict, Russia launched a full-fledged invasion of Ukraine and began occupying many parts of the country, starting one of the deadliest wars in the 21st century. The war resulted in an estimated 1,000,000 casualties until September 2024 during the Ukranian invasion by Russia and also created a refugee crisis. There are efforts to negotiate a peaceful resolution, but the conflict is unresolved, with both countries holding their positions firm, and currently there is a volatile situation.
8. Tigray War (2020 – 2022)
The Tigray War was a civil war in Ethiopia from November 2020 to November 2022 between TPLF (Tigray People’s Liberation Front) and Ethiopian and Eritrean forces. It was one of the most deadliest conflicts in the 21st century. Tensions rose when the TPLF forces attacked the Ethiopian military bases in Tigray. With the support of the Eritrean forces, Ethiopian forces captured Lekelle, Tigray’s capital, in late 2020. However, the TPLF recaptured the city in mid-2021 and extended the fighting into the neighbouring regions of Afar and Amhara. By November 2021, the TPLF and another group called the Oromo Liberation Army threatened to march to Addis Ababa, the capital.
The counter-attack and peace negotiations led to a temporary truce in March 2022, only to be resumed in August. However, in November 2022, a ceasefire was agreed upon, though Eritrea continued occupying parts of Tigray. The Tigray War was deadly as it resulted in mass civilian casualties, sexual crimes, war crimes, and a major humanitarian crisis in that region. Estimates of death ranged between 160,000 to 600,000, and the cost of rebuilding the country is estimated at $20 billion.
9. Israel-Hamas War (2023 – Present)
The Israel and Hamas conflict started on October 7, 2023, and is the fifth war in the Gaza-Israel conflict since 2008. It is among the most intense military conflicts in the region since the 1973 Yom Kippur War and the deadliest, especially for Palestine. The latest Israel-Hamas conflict started when Hamas launched a surprise attack on Israel, breaching the barrier between Gaza and Israel and killing more than 1,100 Israelis and foreign nationals. Around 251 people were held hostage by Hamas to pressure Israel to release prisoners of Palestine.
Israel responded to this attack with bombings and ground invasion starting October 27, 2023, to free the hostages and dismantle Hamas. While the war continues, it has led to massive destruction, with more than 40,000 Palestinians killed and several displaced, affecting all of Gaza’s population. Internationally, there is a call for a ceasefire, with massive protests organised across the globe. One of the most deadliest wars of the 21st century, this conflict has resulted in escalations, including the invasion of Lebanon by Israel in October 2024 and attacks on American military bases that are an ally of Israel. The International Court of Justice is evaluating the genocide accusations against Israel.
10. Israel Hezbollah Conflict (2023 – Present)
The clashes between Hezbollah and Israel have escalated since October 8, 2023, in the Golan Heights and Israel-Lebanon border. This event is a spillover of the Israel-Hamas War and is one of the major escalations between Hezbollah and Israel since the Lebanon War in 2006. Hezbollah, in a bid to show solidarity with the Palestinians after Israel’s airstrikes on Gaza as a retaliation to the Hamas attack, fired artillery and rockets at Israeli bases. Israel responded to it, targeting Hezbollah positions with their precision artillery and rockets. In September 2024, a series of Israeli attacks and Operation Northern Arrows was launched to target Hezbollah bosses and their infrastructure. This killed Hassan Nasrallah, the Hezbollah leader. By October 1, the South Lebanon ground invasion was launched by Israel, intensifying the conflict. This war, like other wars, is not without casualties, with around 1.2 million in Lebanon and 96,000 in North Israel displaced.
Will There Be An End To The Great Battles Of The 21st Century?
As you can see, the world is grappling with the fallouts, and the top 10 deadliest wars of the modern world are proof of this. The 21st century was thought to be a period of technological advancement that could potentially usher in a new era of peace and prosperity. However, these past few decades have been anything but that, with great human suffering and geopolitical upheaval caused by these wars. We can only hope that everyone learns from the horrible mistakes made and works towards a more peaceful world that prioritises human rights, respects the law, and looks for a peaceful resolution for conflicts and disputes.