The East-West Institute released a study in late May by U.S. and Russian 'experts' on the Iranian missile threat that concluded the threat 'is not imminent and that in any event the system currently proposed would not be effective against it.' The next day, Defense Secretary Robert Gates says, Iran apparently tested a multistage, solid-propellant missile with a range of 1,200 to 1,500 miles, putting much of Europe within range. The apparent re-election of Iranian President Mahmoud Ahmadinejad, and his frequently expressed commitment to pursue nuclear and ballistic missile capability, underscore the importance of proposed U.S. radar sites and missile defense interceptors in Eastern Europe. Critics of the plan frequently recycle the arguments repeatedly invoked by Russian diplomatic and defense officials during rounds of U.S.-Russian diplomacy throughout 2007-08, including two meetings between their foreign and defense ministers. That thinking goes: There is no near-term, long-range Iranian missile threat; the proposed U.S. system could not defeat such a threat anyway, but placing that system in Europe will threaten Russia's nuclear deterrent. These tired arguments are not persuasive. Lt. Gen. Patrick O'Reilly, director of the Missile Defense Agency, has recently drawn attention to Iranian progress in staging missiles and moving from liquid to solid propellants. Many critics of the Europe plan acknowledge this progress. An April report of the National Air and Space Intelligence Center noted that 'with sufficient foreign assistance, Iran could develop and test an ICBM capable of reaching the United States by 2015.' Iran's serious search for that kind of assistance was highlighted by New York District Attorney Robert Morgenthau's testimony in May to the Senate Foreign Relations Committee. He recounted the indictment in April of a Chinese business executive for his deals with Iranian defense operatives to transfer: -- 15,000 kilograms of a specialized aluminum alloy used almost exclusively in producing long-range missiles. -- 1,700 kilograms of graphite cylinders used for banned electrical discharge machines. -- More than 30,000 kilograms of tungsten-copper plates. -- 200 pieces of tungsten-copper-alloy hollow cylinders. -- 19,000 kilograms of tungsten metal powder. -- 24,500 kilograms of maraging-steel (high-strength alloy) rods. -- 450 metric tons of furnace electrodes. -- 1,400 metric tons of high-carbon ferro-manganese. At the time of the April indictment, the Iranians were also negotiating to purchase gyroscopes and accelerometers, crucial components for producing ballistic missiles. So could the European site actually defend against the Iranian threat? Critics of the program's likely effectiveness frequently use flawed analytical techniques. The radar the U.S. government has proposed deploying in the Czech Republic has been operated in flight tests in the South Pacific for more than eight years. Critics significantly underestimate its performance, even before its planned deployment upgrades are performed. Nor do detractors understand the basic capabilities of that radar or of the planned forward-deployed radar in acquiring, tracking and discriminating targets. We are taking a multilayer, integrated approach to target discrimination, not just relying on a single element in the chain. The planned interceptors in European silos would provide the fastest and most cost-effective protection against the long-range missiles that Iran is projected to have by 2015. The missile defense program has demonstrated its technical worthiness in flight test after test; 37 of 46 intercepts have been successfully completed in realistic conditions since 2001 by land-mobile, sea-based and silo-based interceptors. After such results, there is no reason to believe the European elements would not work as planned. Russian concerns about the program have always been hard to fathom. How 10 kinetic interceptors with no explosive warhead (much less the nuclear warheads that Russia has deployed around Moscow) can threaten Moscow is simply incomprehensible. The system could handle the small number of ICBMs that Iran might field, but sheer gravity and physics dictate that it could not intercept Russian ICBMs. Gates suggested recently that Russia's threat assessment is evolving and that the country was becoming more inclined to see Iran's program as a threat. That would be a welcome shift. Iran's recent missile test reminds us that its program is moving apace. The United States is deploying a system that will enable us to defend our nation from that emerging threat, but it would be unwise to depart from the long-held proposition that the security and defense of the United States and our European allies are linked. NATO has endorsed the concept of missile defense and bringing its efforts into harmony with the proposed U.S. site. George W. Bush, during his presidency, and now President Obama have endorsed moving ahead as long as there is a threat. The administration and Congress should provide adequate funds to move forward with this project to anticipate the threat rather than dealing with Ahmadinejad and an Iranian missile capability after the fact. Retired Air Force Lt. Gen. Trey Obering was director of the Missile Defense Agency from July 2004 to November 2008. Eric Edelman, a distinguished fellow at the Center for Strategic and Budgetary Analysis, was undersecretary of defense for policy from August 2005 to January 2009. 