Obama's US rejoins nuke treaty conference

— Saying America's "glad to be back," Secretary of State Hillary Rodham Clinton on Thursday rejoined a U.N. conference on the nuclear test-ban treaty after a 10-year U.S. absence from the biennial meeting.

Clinton reported to the gathering of foreign ministers and other envoys from more than 100 nations that the administration of President Barack Obama will "will work in the months ahead both to seek the advice and consent of the United States Senate to ratify the treaty."

The 1996 Comprehensive Test Ban Treaty, or CTBT, which would ban all nuclear bomb tests everywhere, has lingered in a diplomatic limbo since a Republican-dominated U.S. Senate rejected it in 1999, the last year when the U.S. participated in the conference, held every two years to try to win a sufficient ratifications to bring the treaty into force.

The two-day assembly was being held in parallel with Thursday's summit of the 15 U.N. Security Council members on the subject of nuclear nonproliferation, presided over by Obama, who has pledged to work toward a world free of nuclear weapons.

"There is no better way to begin this historic day than to pledge to end nuclear testing," U.N. Secretary-General Ban Ki-moon told the treaty conference.

The ministers adopted a declaration saying the CTBT's entry into force is "more urgent today than ever before."

"We call upon all states which have not yet done so, to sign and ratify the treaty without delay, in particular, those states" — which includes the U.S. — "whose ratification is needed for entry into force," it said.

The CTBT opponents in the Republican-dominated Senate of 1999 objected that the U.S. might need to test its weapons to ensure the reliability of its nuclear stockpile, and contended that a planned International Monitoring System underpinning the treaty might fail to detect secret tests by nuclear cheaters.

Obama announced last April that the U.S. would "aggressively" pursue ratification. But even in the current, Democratic-majority Senate, proponents might have difficulty winning the required two-thirds vote for the treaty, expected to come up for consideration next year.

Treaty supporters point out that this time around the treaty monitoring system is not simply a blueprint, but a working, $1-billion network of high-tech stations on alert for secret nuclear tests.

Experts of the U.S. National Academy of Sciences are studying the effectiveness of the verification system, along with the reliability of the U.S. nuclear stockpile without testing, and will report their findings this winter.

Tibor Toth, who heads the U.N.-affiliated Comprehensive Test Ban Treaty Organization, said he hoped this "nonpartisan" review will reassure enough Republicans to win the needed 67 votes for the pact.

The CTBT requires ratification — that is, full government approval — by 44 states with nuclear weapons or technology before it can take effect. All but nine of those have ratified, along with the governing bodies of 115 other nations.

Besides the U.S., the holdouts among the 44 are China, Egypt, India, Indonesia, Iran, Israel, North Korea and Pakistan. Meanwhile, the U.S. and four other original nuclear powers — Russia, Britain, France and China — have observed testing moratoriums.

Speaker after speaker on Thursday predicted that a U.S. ratification would prompt at least some other holdouts to support the treaty. The CTBT "was never before so close to entry into force," said French Foreign Minister Bernard Kouchner, conference co-president.