A top U.S. Defense Department official April 6 dismissed North Korea's rocket launch a day earlier as a failure technologically and as a marketing tool for contraband missile sales to other countries.

"Would you buy from somebody that had failed three times in a row and never been successful?" Gen. James Cartwright, vice chairman of the Joint Chiefs of Staff, said during a briefing at the Pentagon.

The abortive missile launch, Cartwright said, showed that North Korea had failed to master the in-flight thrust shift from one rocket booster to another, an integral part of intercontinental ballistic missile technology.

North Korea's attempted launch of a three-stage rocket April 5 demonstrated only one minor victory: It went twice as far as one launched in 1998.

In diplomatic circles, whether Pyongyang is technically any closer to having a working ICBM is immaterial. Just the attempt defied a United Nations Security Council resolution that warned North Korea against a launch.

Security Council members met for three hours April 5 but failed to release even a customary preliminary statement of condemnation, evidence of the challenges in agreeing on any kind of punishment. China, the North's closest ally, and Russia hold veto power, and could water down any response.

U.S. Secretary of State Hillary Rodham Clinton said April 6 that she is lobbying key members of the Security Council to respond to the launch, which she called "a provocative act that has grave implications."