Iran and the U.S. need a way to communicate As the United States and Iran move closer toward open confrontation, it's important that both take quiet steps to avoid the miscalculations and misunderstandings that can lead to an inadvertent military conflict. It's been done before: During the Cuban missile crisis in 1962, President John F. Kennedy used a back channel to communicate U.S. resolve to the Soviets and also explore a formula for settlement. The key points of contact were his brother, Attorney General Robert Kennedy, and the Soviet ambassador to Washington, Anatoly Dobrynin. That exchange helped avoid nuclear war. Today Washington and Tehran lack any similar means of communication in a crisis. Since the embassy takeover that followed the Iranian revolution of 1979, the two nations haven't had diplomatic recognition. They communicate indirectly, through the Swiss embassy, which is inadequate. So here's a proposal in this period of deepening crisis: The United States and Iran should explore the possibility of direct contact through the sort of back channel that nations use to communicate urgent messages -- namely, their intelligence services. Through this contact, each side could communicate its "red lines" in the crisis -- for the United States, the insistence that Iran's nuclear program remain peaceful; for Iran, presumably, an end to sanctions and a recognition that Iran is a significant regional power. My nominees for this back-channel contact would be two people who have been circling each other warily for the past half-dozen years: Gen. David Petraeus, director