The A.Q. Khan network has been described as the "Wal-Mart of private sector proliferation for the world." its handiwork has helped deliver to us two of the most threatening security challenges faced in the West, one is North Korea and the other is Iran.

A.Q. Khan, the so-called father of Pakistan's bomb, for over a decade ran a sophisticated and multinational clandestine network built around Pakistan's own nuclear weapons program, which provided advanced nuclear enrichment technology and expertise to a number of hostile countries, as well as to Libya, and perhaps others.

In October 2003, Italian authorities seized sophisticated centrifuge components bound for Libya aboard the ship BBC China, forcing the Pakistan Government and President Musharraf to confront A.Q. Khan and to confront A.Q. Khan's cohorts publicly. This should have been done years earlier.

Khan's network has done incalculable and potentially catastrophic damage to international security. It has opened an era in which many states, including among the most unstable and most hostile to the U.S., can now expect to develop nuclear weapons. This is the grim legacy of A.Q. Khan.