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Despite the disadvantages, Iraq could have decided to pursue aluminum rotors because it could get the aluminum tubing easier than those other materials. Unlike outer casings, aluminum rotor assemblies do not require welding, therefore the 7000 series aluminum could be used for rotors. Iraq may also feel more confident making aluminum rotors than maraging steel or carbon fiber rotors. Iraq's extensive knowledge of early German and Urenco centrifuge designs enable it to modify its established Zippe-type designs to use aluminum rotors. Iraq's use of this design is more likely than a Beams-type design, given its knowledge and experience.

The dimensions of Zippe-type centrifuges made with aluminum rotors are publicly available. The rotors typically have diameters between 50 and 100 millimeters and a length of about 50 centimeters.3 Their wall thickness was less than one millimeter. Thus, the dimensions of the aluminum tubes Iraq sought are consistent with a centrifuge use, assuming that the tubes would be cut and the walls significantly thinned. Zippe-type centrifuges that used aluminum rotors in the late-1950s and the 1960s used a T6 hardening. As a result, cutting would not present any obstacles. Whether two rotors could be made from each tube is unknown, however. In addition, the special hardening would permit the tubing wall to be shaved down to the required thickness for a centrifuge rotor. A good tool, however, would be required to thin the tube thickness to about 0.5 millimeters.

The aluminum tubes Zippe used were not anodized or did not have any other type of coating. Uncoated aluminum works well in a centrifuge both as a rotor and cascade piping. The coating on the outer surface of the tube would be removed during the shaving operation. An anodized layer on the inside of the tube, however, should work fine in a centrifuge, according to an expert involved in the development of Zippe-type centrifuges in the 1950s and 1960s.

Instead of an pure aluminum rotor, Iraq could also pursue a hybrid design that involves wrapping carbon-fiber or another composite material over an aluminum tube. However, in this case the aluminum tube does not need to be as strong as 7000-series aluminum.

The use of the tubing was investigated by the U.S. Army National Ground Intelligence Center. It concluded that the use of this particular high strength aluminum tubing would have been "exquisite," far in advance of what is needed for a MRLS. One knowledgeable expert, however, said that the Ground Intelligence Center did not receive all the information.

This expert said that Iraq imported 7000-series tubing for non-nuclear uses in the 1980s and 1990s. Thus, these recent attempted procurements could also have been intended for a non-nuclear use.

The debate over the purpose of the tubing left some dissenters perplexed. "Always the same answer, no matter what the objections were," one said. Inevitably, this situation led to speculation. Did the CIA have information about the tubes it was not sharing to protect important secrets? Or was the CIA arguing a view not really based in the facts? The recent statements emanating from the CIA suggest that it is not as certain about the intended purpose of this shipment, as first stated.