WASHINGTON — President Obama sent a secret letter to Russia’s president last month suggesting that he would back off deploying a new missile defense system in Eastern Europe if Moscow would help stop Iran from developing long-range weapons, American officials said Monday. The letter to President Dmitri A. Medvedev was hand-delivered in Moscow by top administration officials three weeks ago. It said the United States would not need to proceed with the interceptor system, which has been vehemently opposed by Russia since it was proposed by the Bush administration, if Iran halted any efforts to build nuclear warheads and ballistic...
