The late 20th century produced a memorable crop of visionary men and women - among them, Mandela, Aquino, Walesa - who risked their lives to stand up for freedom, equality, and democracy against ruthless rulers.
Many won the day with their nonviolent methods and were elected into office. But eventually, like all heroes, they must fade from the scene.
The latest example is Vaclav Havel, the president of the Czech Republic who stepped down from office this week. This playwright and author used the power of ideas to oppose the communist rulers who threw him in jail, only to see him become president in a liberated country after the "Velvet Revolution" in 1989.
Thirteen years later, Mr. Havel leaves behind a country that's free, but now politically adrift and unsure of itself.
Such is often the case with many of the brave, inspiring dissidents who came to power in recent decades, but were unable to transform their countries quickly. They raised popular expectations, and perhaps left the impression that change will come from on high, when real change comes from the people themselves.
Like Havel, the president of South Korea, Kim Dae Jung, was a thoughtful, courageous dissident who suffered much but was elected to power once he helped bring democracy to that country in 1987.
Mr. Kim, too, leaves office this month, with democracy solidly in place But he failed in many of his reforms, such as his "sunshine policy" toward North Korea. Also like Havel, he has a reputation much diminished among his own people.
Despite lost glory at home, both Havel and Kim will likely join that band of former great leaders who often speak out on international issues. Nelson Mandela of South Africa and Cory Aquino of the Philippines still command a presence in the world for their integrity and experience.
By staying in the public eye, they serve as a reminder of other dissidents who are following in their path. In Burma, for instance, Aung San Suu Kyi led a nonviolent revolt against military rule in 1988 and won an election, only to see the results ignored and herself put under house arrest for years. In China, longtime democracy advocate Xu Wenli was just released from jail (again) and sent into exile.
Unfortunately, few of the countries that remain under dictators have such brave leaders, or they just aren't allowed to emerge. Iraq could use someone right now who could make the difference between war and peace.
The title of Havel's most famous anticommunist essay, "The Power of the Powerless," was the kind of message of hope that people under suppression need to hear. He and others like him leave a legacy to live up to.