(NewsNation) — Though hesitant to build a relationship at first, President Ronald Reagan formed a professional bond with former Soviet leader Mikhail Gorbachev that led to the end of the Cold War and continues to stand as a benchmark for geopolitical relationships.

In the last days of Reagan’s life, Gorbachev called the former president “a statesman who, despite all disagreements that existed between our countries at the time, displayed foresight and determination to meet our proposals halfway and change our relations for the better.”

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“I deem Ronald Reagan a great president, with whom the Soviet leadership was able to launch a very difficult but important dialogue,” the Interfax news agency quoted Gorbachev as saying on Ekho Moskvy radio.

But their relationship took time to build, as the two had polar opposite political views and preconceived opinions of one another.   

Reagan, who died 20 years ago this week, was an anticommunist capitalist who vowed to stop the Soviet Union’s “evil empire” when taking office, according to the History Channel.  

Gorbachev was a committed communist who rose through the political ranks to lead the Soviet Union.

But as the Cold War progressed, the two realized they needed to communicate. They wrote letters to each other to suppress a rapidly evolving nuclear arms race. 

According to the History Channel, more than 40 letters, many handwritten, and four summits in just over three years were key to building that trust. 

 “As I look back on them now, I realize those first letters marked the cautious beginning on both sides of what was to become the foundation of not only a better relationship between our countries but a friendship between two men,” Reagan wrote in his autobiography, An American Life. 

That willingness to negotiate has been praised for helping end the Cold War. Together, they negotiated a landmark deal in 1987 to scrap intermediate-range nuclear missiles.

Historian Jason Saltoun-Ebin closely studied the relationship between the two and credits their ability to overcome their reluctance towards each other as crucial to stopping war.

“Perhaps then the real story of the end of the Cold War is just a simple tale of how an old hard-line anticommunist president of the United States and a young Soviet reformer discovered that, despite their vast differences, all they needed to do was find one common area of agreement to change the world,” he wrote in his book, “Dear Mr. President…: Reagan/Gorbachev and the Correspondence that ended the Cold War.” 

“Both Reagan and Gorbachev recognized that change was coming, and both wanted to be on the right side of history,” he wrote. “But they needed to find a way to overcome forty years of Cold War ideology. They needed to find a way to trust each other.”

It’s a trust that feels almost impossible in present-day politics. 

“I think, frankly, (that) President Gorbachev and I discovered a sort of a bond, a friendship between us, that we thought could become such a bond between all the people,” Reagan told journalists in Moscow during a visit in 1990.

When Reagan’s son Michael attended his father’s funeral, Gorbachev was sitting right behind him, reported The Guardian. 

“What I most remember is him telling me that every time my father and him met, my father would always end every meeting with, ‘If it’s God’s will’, and Mikhail Gorbachev would say to me, ‘I would look around the room to see if God was there’.”