Schoolboy Nick Clegg organised extra classes while at school in a bid to prepare Britain's response to the Soviet threat.
Writing in response to a politics.co.uk questionnaire, the Liberal Democrat leader explained that while the Falklands War and the miners' strike had had a big impact, it was the prospect of invasion by communist forces which first mobilised him.
"I remember being scared witless as an 11-year-old by a fire-and-brimstone history teacher who told us we would all be dead by Christmas because the Soviet Union urgently needed access to warm water ports for some reason, and the Red Army was going to sweep through Europe," he wrote.
"I was so alarmed I insisted on extra classes so we could work out what to do."
Mr Clegg was aged 11 in 1978, a period of relative détente between the superpowers.
The Cold War has shaped the Lib Dem leader's outlook in other ways, too. He chose Czechoslovakian leader Vaclav Havel as his favourite political figure, saying he admired the courage of the Velvet Revolution figurehead.
"Despite spending years in prison and being constantly harassed after his release, he didn't falter in his determination to change his country's government, and to uphold his commitment to non-violent resistance," Mr Clegg wrote.
"I had the huge good fortune to meet him in Prague while I was working on the Czech Republic's application to join the EU. He didn't disappoint."
Mr Clegg worked in Europe for ten years after beginning his working life with "a bit of journalism". He administered aid projects for some of Asia's poorest countries before negotiating trade deals with China and Russia on behalf of the EU. Finally, in 1999, he represented the East Midlands as an MEP.
"I work hard, and, whatever I do, I do it because I believe it's right," he added.
"It's not always easy to balance being the leader of a party and a good constituency MP, but I make sure I'm available to my constituents. And when I'm helping them with their problems I'm like a dog with a bone - I don't let things lie."
Elsewhere in the questionnaire, he revealed his favourite political film is Gandhi. His favourite political song is Pink Floyd's The Wall.
Mr Clegg, asked to sum up his beliefs in one sentence, stated: "If you want things to be different, you have to do things differently."