By Tom Bemis Former U.S. Secretary of State warns we are in a ‘totally new era.’ Former U.S. Secretary of State Henry Kissinger says the world must consider how to react if Russian dictator Vladimir Putin decides to use nuclear weapons in his war on Ukraine. “If that line is crossed, that would be an extraordinarily significant event,” Kissinger said during an interview at a weekend conference sponsored by the Financial Times. “And we have to think of how to react were it to happen,” he added. Kissinger, who served as Secretary of State in the Nixon administration, said the ongoing spread of n…