The greatest challenge for big-power diplomacy today is non-proliferation, keeping shut the door to the nuclear club.

NPR: U.S. Loses Its Edge in Nuclear Talks

Prime Minister Ehud Olmert reportedly told his ministers that Israel needs to develop contingencies for the day after Iran joins the nuclear club.

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But the effect is to make India the sixth member of the nuclear club, and that's a big blow to the cause of non-proliferation.

NPR: Week in Review: India; Guantanamo; Iraq; FEMA

At that time there were no more than 30 qualified nuclear physicists in the country, far fewer than China needed to join the nuclear club.

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Libya has resigned from the nuclear club.

NPR: Weak Prospects for Nuclear Nonproliferation Efforts

We also speak exclusively to Mohamed ElBaradei, Director General of the IAEA, the man caught in the diplomatic crossfire between states eager to join the nuclear club, and those already in who do not trust the outsiders to play safe.

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Neither country, it was said, would be accepted into the club of official nuclear powers.

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It wants recognition by the other nuclear powers that it is now one of the club, and the promise of an end to sanctions if it signs the treaty.

ECONOMIST: India and Pakistan

It essentially says: Those countries that have nuclear weapons can keep them, but no one else can join the club.

CENTERFORSECURITYPOLICY: Test-Ban Trap

"A real exit strategy has to start with an inspection by the world's top experts on nuclear accidents, " Iida told reporters at Japan's national press club last week.

CNN: STORY HIGHLIGHTS

Once in the club, with full voting rights, countries can answer back, leaving their peers with only the nuclear option of trying to expel them.

ECONOMIST: Romania and democracy