Margaret Thatcher and Ronald Reagan courted Mikhail Gorbachev in the 1980s, as they planned to end the Cold War.
It was all about the right people at the right time. Their cooperation dramatically altered the international landscape.
Jon Craig is chief political correspondent
Mrs Thatcher referred to Gorbachev, even before he was elected leader of the Soviet Union. She did just that, with Ronald Reagan, her ideological soulmate.
In 1984, Mr Gorbachev visited the UK to meet her. This was at a time when the USSR was expecting him to become the next head of state.
Mrs Thatcher wanted to have better personal relationships with him and with the Soviet Union.
Many will find it tragic that her warm relations with Gorbachev during the 1980s which led to the end of the Cold War and the fall of the Berlin Wall, as well as the creation of modern democracies throughout Eastern Europe, are now in ruins by President Putin’s brutal war against Ukraine.
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Mrs Thatcher literally laid the red carpet for Gorbachev on his 1984 visit to the UK, when he was hosted at Chequers. He was the Soviet Communist Party’s Number 2 at that time.
Later, Mrs Gorbachev’s predecessor in office, President Chernenko, was laid to rest. She told the new president that his 1985 visit was one of the most successful by any major world leader.
No British prime minister met more Soviet leaders than Mrs Thatcher with Mr Gorbachev. Winston Churchill, her wartime ally Josef Stalin, was not her hero.
The diplomatic result was the glittering diplomat prize of the thawing Cold War. Mrs Thatcher, Mr Gorbachev and all of them must be credited greatly.
Mark Stone, US correspondent
He was the last Soviet leader and so different from the others. For the man who made a huge leap and changed the world, these were some of the most popular adjectives used in the West. The world map was changed by his efforts in just five years.
Even his nickname, ‘Gorby’, evokes fondness. However, the truth is that his legacy and reflections of him will be different.
His London-based obituary will look very similar to the one written here in Washington. It will be different in the Baltic countries, which once saw Gorbachev’s tanks come in, because it is written differently. Moscow will have some reflections that are different from the rest.
In 1991, he stated that society had “acquired freedom” through his perestroika reform program. He is undoubtedly the West’s hero. He liberated eastern Europe and brought Germany back together.
Oder, was he the one who lost an empire. Putin would like to put it back together. Different histories in different places.
It’s the images that give you a sense of the person and the time. This is regardless of which version of history you’re reading.
A picture of him and Ronald Reagan spoke volumes to me. It was taken at Reagan’s ranch, California. Both men were wearing cowboy hats.
Their smiles were a sign of the unusual relationship between capitalists and communists; two men who managed to bring two superpowers back from their brinks, through the Cold War, and out on the other side.
Gorbachev, the USSR’s leader, resigned on 25 December 1991 and gave control over the Russian nuclear arsenal (under Boris Yeltsin) to his successor. According to legend, he said to Reagan’s successor George HW Bush that he could have a quiet Christmas evening.
The Cold War was over, the threat had vanished. Or so we thought. It’s amazing how times have changed.