A history of the events that caused the Berlin Wall to fall on November 9, 1989.
Twenty years later, the rest of the world is a different place because of that event.
A European Union agreement last week was short on specifics. US commitments on reductions may not be forthcoming, making Chinese commitments also unlikely.
Exiled Poles were sent to Persia, as one woman discovers in tracing her grandmother's journey to America.
Strategists say that President Barack Obama's decision to scrap a controversial missile shield for Eastern Europe has mollified Russia, and could open the door for cooperation against common nuclear threats.
Selections from 85 immigrants tell what it means to become an American.
US Vice President Joe Biden toured Eastern Europe this week with a new missile-defense plan designed to reassure the Czech Republic and Poland that they aren't being forgotten as relations warm with Moscow.