Ronald Heifetz has been a professor of public leadership at Harvard's Kennedy School for three decades, teaching classes that have included aspiring business leaders and budding heads of state. Each year, he says, the students start his course thinking they'll learn the answer to one question:
As leaders, how can they get others to follow them?
With a Swiss forensics investigation pointing to polonium-210 as a possible cause of Yasser Arafat's death, the radioactive element is back in the news.
Confirming whether the Palestinian leader died from an assassination attempt will be difficult, given polonium's short half-life and the fact that Arafat has been dead nine years, science writer Deborah Blum says.
Whatever happened to Arafat, polonium does have a deadly history.