While aging survivors pray for peace and vow never to forget the attacks that killed more than 210 000 people, the weapons they abhor remain at the centre of the international stage.

The apocalyptic arms have turned into status symbols for aspiring powers whose nuclear ambitions can bring them either international isolation or generous rewards, depending on how shrewdly they play their cards.

North Korea has boasted of an atomic arsenal, Iran is defiantly vowing to resume nuclear activities, and the scientist who built the Islamic world's first atomic bomb in Pakistan shared secrets with both nations — and Libya.

In a sign that going nuclear no longer means pariah status, the United States last month lifted a ban on civilian nuclear sales to India, which has never signed up to global non-proliferation rules.

The wrong hands

And some of the deepest fears now are not over governments, but about nuclear weapons getting into the hands of groups such as al-Qaeda, for which international treaties are not even a consideration.

"The nature of the threat associated with nuclear materials has changed and the whole international regime to cope with the threat has not kept pace to respond," said Kuniko Inoguchi, Japan's former ambassador for disarmament.

"Today the threat is much more unexpected in nature," she said. "Just as in the war against terror, this is a new war, a new kind of proliferation, a new kind of security threat. And the common feature is that you don't really see with whom you should negotiate or against whom you are fighting."

'I really have no reason to be optimistic'

Ten years ago on the 50th anniversary of the bombings, opponents of nuclear weapons had reason to feel optimism. The collapse of the Soviet Union meant the world was no longer divided between two nuclear powers whose conflict could bring the world to the verge of Armageddon.

But since then at least two more nations have gone nuclear — India and Pakistan — and there is no sign the six other nuclear nations — the United States, Russia, Britain, China, France, India and Israel — are giving up their arsenals.

Keeping mum

Meanwhile there are many more, including atomic victim Japan, which stay mum on the question of nuclear weapons as they are under the US security umbrella.

"I really have no reason to be optimistic," said Jean du Preez, a former South African diplomat active in disarmament.

A UN conference in May on the nuclear Non-Proliferation Treaty failed to make any major revisions despite repeated warnings that the 1970 agreement was out of date.

Du Preez, who heads the International Organisations and Non-proliferation Programme at the Monterey Institute of International Studies in California, said the conference showed the world could not even take a first step.

"Non-proliferation is only a means to prevent the threat of nuclear weapons. It is not the ultimate goal — that is to get rid of nuclear weapons," he said.

The United States invaded Iraq in 2003 and one reason given by US President George W. Bush, although never proven, was that Saddam Hussein was going nuclear.

In one example Washington has cited as a success, Libya later that year agreed to give up its weapons of mass destruction in exchange for returning to the international community.

North Korea, Iran, India & Pakistan

But the standoff over North Korea's nuclear programme has lingered on for more than a decade.

"They have probably developed nuclear weapons in that time without facing any sanctions from the (UN) Security Council and are now in a situation where they might be able to extract a deal from the United States," Du Preez said.

"Look what's happening with Iran. It's basically dictating the pace of how it will dismantle or freeze its program," he said.

Tehran's latest move in restarting nuclear activities was "clearly to send a signal to their European partners -- you better pay up or else," he said.

An Iranian press report last month cited an unnamed official accusing the United States of double standards on its nuclear cooperation deal with India.

It was a sign, the Tehran official said, that Washington would not press on nuclear weapons if it liked the country involved.

India stunned the world in 1998 when Atal Behari Vajpayee, the nation's first Hindu nationalist prime minister, ordered a nuclear test. Vajpayee, a poet who had had written about the horrors of Hiroshima, declared New Delhi part of the nuclear league.

Pakistan responded 17 days later with tests of its own. Both countries came under international sanctions, but they were lifted when the South Asian rivals became allies in the US-led "war on terrorism" after the September 11, 2001 attacks.

India's profile has only risen since it went nuclear, moving closer to the United States and becoming a leading contender for a permanent seat on the UN Security Council.

Praful Bidwai, an Indian columnist and anti-nuclear activist, said the new agreement between New Delhi and Washington on nuclear trade was "certainly a setback to a nuclear free world" by narrowing "the penalty for crossing the nuclear threshold".

"This is sending the wrong message to a number of states including some that had foresworn nuclear weapons," Bidwai said. "They're going to feel let down." Nuclear memories start to fade

Every year at Hiroshima and Nagasaki, local leaders pledge to work to abolish nuclear weapons before the last survivors die. Every year, there are fewer survivors. Nagasaki Mayor Iccho Ito, in an interview with AFP, called on North Korea to end its nuclear programme as part of a nuclear-free Northeast Asia.

"Everybody knows it is too dangerous to use nuclear weapons, which can wipe out the human race instantly," Ito said.

But 60 years after Hiroshima and Nagasaki were demolished, some — like Du Preez, the non-proliferation expert — wonder if awareness of the horrors of nuclear war has already begun to fade.

"The point is that another generation or so away, people are going to start forgetting about what nuclear weapons can really do," he said.

AFP