I could have used this quote, from Henry Kissinger, at my recent Intelligence Squared debate in which I argued, with Shmuel Bar, against the motion that Israel could live with a nuclear Iran:

"The danger is that we could be reaching a point where nuclear weapons would become almost conventional, and there will be the possibility of a nuclear conflict at some point... that would be a turning point in human history," he said.

This is the biggest worry of all: That a nuclear arms race in the world's most volatile region leads to a kind of quick-draw, launch-on-warning approach by multiple nations, ending in an accidental conflagration. Kissinger:

"For 15 years, the permanent members of the United Nations Security Council (UNSC) have declared that a nuclear Iran is unacceptable, but it has been approaching," he said. "In a few years, people will have to come to a determination of how to react, or the consequences of non-reaction.... I believe this point will be reached in a very foreseeable future," he added.

Here, by the way, is a link to the Intelligence Squared debate, which is worth watching, and not only because my team won.