Anti-nuclear activist Helen Caldicott warned of a continuing global threat posed by U.S. and Russian nuclear stockpiles. In her speech in Portland on Saturday, Caldicott said the former Cold War rivals still have thousands of nuclear weapons aimed at each other and a single mistake could result in mutual annihilation. “Anything that happens in the world that triggers anxiety could blow us all off the face of the Earth,” Caldicott said. “No one knows about it now. In the eighties, people were scared out of their brains.” The 65-year-old Australian activist and author spoke mainly about problems of command and control, especially inside Russia’s aging nuclear program. She said problems with nuclear weapons programs could lead to a mistaken belief that the country is under attack, prompting a decision to launch a retaliatory strike. Caldicott, who lives in Washington, D.C., was nominated for the Nobel Peace Prize in 1985