Despite Iran's runaway nuclear program, North Korea's atomic assistance to Syria, and robust ballistic missile production and testing by Russia and China, a missile defense system for protecting the homeland and U.S. interests overseas remains a controversial idea in some corners. It should not be. The security challenge arising from the proliferation of ballistic missiles and the dangerous payloads they might carry, including weapons of mass destruction (wmd) like nuclear arms, is a threat that — in fact — may be growing.

While the Bush administration has taken significant steps to develop sea- and land-based missile defense systems, the next White House and Congress should continue supporting missile defense programs to enhance our national security. Indeed, just this summer, the Washington Post broke a story claiming the international nuclear smuggling ring once run by the prodigious Pakistani proliferator A.Q. Khan had also managed to acquire the blueprints for an "advanced nuclear weapon."

Owned by three Swiss members of Khan's international cabal, a laptop containing 1,000 gigabytes of data (roughly equivalent to the information contained in a local library) on designs and engineering for nuclear weapons was discovered by investigators. Regrettably, according to the story, the United Nations' International Atomic Energy Agency (iaea) believes the nuclear weapons designs found on the laptop could be mated — in theory — to the ballistic missiles used by "more than a dozen developing countries."

In fact, the iaea, which reportedly verified the destruction of the data by Swiss authorities, cannot guarantee the nuclear warhead designs were not shared with others, according to a report by David Albright, a weapons expert who has been investigating the Khan network. While North Korea, Iran and Libya — the three states with which Khan had the most intimate contact — are the most likely recipients of the Pakistani's atomic assistance, there may be others who received this nuclear know-how as well, although some experts view the report as alarmist. (Not surprisingly, Khan, who has been under house arrest in Pakistan since 2004, denied that he was involved in any way in proliferating nuclear weapons designs. Of course, others in his nuclear network may have done so.)

With Israel's strike on a suspected Syrian nuclear site in September 2007 and news of nuclear power programs popping up across the Middle East (which may be hedging against Iran's nuclear efforts), this sort of dire speculation about possible proliferation makes security experts increasingly nervous. Indeed, the ballistic missile and nuclear proliferation trend is not positive. Ten years ago, there were only six nuclear-weapons states. Today there are nine members of the once-exclusive nuclear-weapons club, with Iran perhaps knocking at the door. Twenty-five years ago, nine countries had ballistic missiles. Today there are 28 countries with ballistic missile arsenals of varying capability.

Iranian intrigue

Among present proliferation problems, Iran may be the most troubling to American security analysts, especially considering its longstanding enmity toward the United States, sponsorship of terrorism, involvement in Iraq and Afghanistan, and regional great-power ambitions.

Tehran, naturally, insists its burgeoning nuclear program is for little more than peaceful power generation, designed to augment Iran's already significant oil and natural gas reserves. (Iran has the world's third largest oil and second largest natural gas reserves.) But like a sledgehammer, new intelligence continues to blast away at Iran's rock-like insistence that its nuclear program is purely peaceful and not a weapons effort as many in the region and beyond increasingly believe.

The most serious blow comes out of the United Nations' nuclear watchdog in Vienna, the iaea, which drafted and released a troubling nine-page report in late May casting serious doubt on Iran's claims to a purported pacifist power program. In a dramatic change, based on new multi-source, multilateral intelligence received over time from a number of its member states, the iaea has shifted its position from being unable to prove Iran has a nuclear weapons program to being unable to prove Iran does not have one. (Indeed, in late June, iaea chief Mohamed El Baradei commented on Arab television that Iran could build a nuclear weapon in six months to a year if it decided to do so, considering its current centrifuge capacity and the quantity of processed uranium it already has on hand.)

Ten years ago, there were only six nuclearweapons states. Today there are nine, with Iran perhaps aiming to be the tenth.

Based on 18 hard-copy and electronic documents, the nuclear-monitoring agency expressed concerns about the increasingly questionable nature of Iran's nuclear program, especially its possible military dimensions, which would violate Iran's Nuclear Non-Proliferation Treaty (npt) commitments. (The npt allows signatories to pursue nuclear programs for scientific or power purposes, but not military ends, which include weapons production. All activities must be declared to the iaea. Of note, not all states have signed the npt, most notably India, Pakistan, and Israel; North Korea withdrew.)

In its first formal assessment of Iran's nuclear efforts since February, the iaea states in the most "diplomatic" of terms: "The agency [iaea] is of the view that Iran may have additional information, in particular on high explosives testing and missile-related activities, which could shed more light on the nature of these alleged studies and which Iran should share with the agency."

The iaea considers these unanswered questions on Iran's nuclear work "a matter of serious concern" because the existence of this sort of activity might indicate Tehran is secretly developing a nuclear weapon, contrary to Iran's repeated public protestations. Moreover, the report states, "Iran has not provided the agency with all the information, access to documents and access to individuals necessary to supports Iran's statements," despite the new intelligence, which is "detailed in content, and appears to be generally consistent."

The first charge is that Iran is suspected of conducting high-explosives testing. This includes work with exploding bridgewire (ebw) detonators and a detonator firing unit, which could be used for triggering a nuclear weapon; 500 ebw detonators were tested, according to the iaea.

In addition, a five-page document describes experiments for a "complex multipoint initiation system" to "detonate a substantial amount of high explosive in hemispherical geometry" that could be employed in an implosion-type nuclear device. Tehran is further accused of developing plans for underground explosives testing, which could be utilized for detonating a nuclear weapon similar to the testing done by North Korea in October 2006. The documents also include a technical diagram for a "400m deep shaft located 10km from a firing control point," showing "the placement of various electronic systems such as a control unit and a high-voltage power generator."

It seems military-related institutions are involved in procurement activities for Iran's "peaceful" nuclear power program.

There is also a mysterious piece of information the iaea  report calls the "uranium metal document," which is related to the "actual design or manufacture by Iran of nuclear material components of a nuclear weapon." The document allegedly describes procedures for machining highly enriched uranium metal into a hemispherical shape, key to producing the rounded "pits" used in modern implosion-type nuclear weapon warheads. Strikingly, the report notes that "Pakistan has confirmed, in response to the Agency's request, that an identical document exists in...