Russian forces are closing in on Ukranian capital Kyiv from three sides in what is being described as the biggest attack on a European state since World War II.

While outlining US observations of the conflict earlier on Thursday, a senior defence official said the Russian invasion of Ukraine was the largest conventional military attack seen since World War II.

"We haven't seen a conventional move like this, nation-state to nation-state, since World War II, certainly nothing on this size and scope and scale," the official said. The military operation holds the potential to be “very bloody, very costly and very impactful”, the official said.

As on Friday morning, only 30 percent of the 150,000 to 190,000 Russian troops massed at the Ukrainian border earlier had entered the country, US defence department officials said.

Here’s a look at five instances where a country either interfered in politics and conflicts of another or simply invaded.

Korea

The Korean War started on June 25, 1950, when the North Korean People's Army, advised by the Soviet Union, invaded South Korea after five years of simmering tensions on the peninsula. North Korea attacked South Korea with the aim of unifying the country under the communist North Korean regime. The United Nations, with the US as the principal participant, assisted the southern Republic of Korea in its defence. China came to the aid of North Korea. After losing around 2.5 million lives, the war ended in July 1953 with Korea still divided into two hostile states. The Korean War was one of the biggest conflicts in the Cold War era between the US and Russia. The war was the first test of the United Nations as a military entity.

Afghanistan

The US and the UN coalition forces invaded Afghanistan after they refused to turn over Osama bin Laden, who was responsible for attacking the United States on 9/11. President George W Bush authorised the use of armed forces against those responsible for the 9/11 attack. The Taliban government was ousted and several terrorist camps destroyed in Afghanistan. However, the Taliban regrouped and launched a scathing attack on the coalition troops. Violence increased in 2006 with a higher number of suicide attacks and remotely detonated bombings. In 2011, US troops and CIA operative tracked Osama bin Laden in Abbottabad, Pakistan, and shot him. In 2012, US President Barack Obama signed a partnership agreement with his Afghani counterpart Hamid Karzai that provided for US forces to remain in Afghanistan after 2014 for the purpose of training Afghan forces and targeting the remnants of al-Qaeda.

In April 2021, President Biden announced that the US will fully withdraw troops by September 11, 2021. “It’s time to end America’s longest war,” Biden said. On August 15, 2021, Taliban fighters captured Kabul and took over the administration in the country.

Iraq

The US and Great Britain invaded Iraq in 2003 with the aim of destroying the so-called weapons of mass destruction and end the dictatorial rule of Saddam Hussein. The intelligence on weapons of mass destruction proved to be illusory, which gave rise to violent insurgency for several years in Iraq. Saddam Hussein was captured and hanged and democratic elections were held in Iraq. In 2011, President Barack Obama announced that the remaining US forces would be withdrawn from Iraq by the end of the year, marking a conclusion to the nearly nine-year war.

Vietnam

A part of the Cold War confrontation, the Vietnam War hung heavily over the 1960s and early 1970s. Although it did not involve a direct confrontation between the two superpowers, the US and the Soviet Union, it was characterised by conflicts that left millions dead. In the heart of the US military intervention was the motive to curtail the influence of Communism in South-East Asia. The war began in 1955 with communist North Vietnam invading non-communist South Vietnam with the aim of unifying the country. The US joined the war in 1961 and finally withdrew combat troops in 1973. In 1975, North Vietnam successfully took over South Vietnam.

Bangladesh

The Bangladesh Liberation War or War of Independence was an armed conflict for nine months in 1971 between former West Pakistan (now Pakistan) and East Pakistan (now Bangladesh). The war resulted in the independence of Bangladesh, which had been part of Pakistan since the Partition of India in 1947. In 1971, former Indian Prime Minister Indira Gandhi decided to intervene in the war to tackle the mass refugee influx into India. Pakistan launched a pre-emptive strike on Indian Air Force bases in December 1971, a strike viewed by India as an open act of unprovoked aggression. This marked the official start of the Indo-Pakistan War. After carrying out several sorties against Pakistan, the Indian armed forces established its dominance in the country. On December 16, 1971, 93,000 Pakistani troops surrendered to the Indian and Bangladeshi forces, making it the biggest surrender since the Second World War. This marked the end of the Bangladesh Liberation War and gave birth to Bangladesh.

Also Read | Explained: How time ran out for US in Afghanistan

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(Edited by : Thomas Abraham)

First Published:Feb 26, 2022 1:12 PM IST