This week sees the start of a five-yearly review of the nuclear non-proliferation treaty and fireworks can be expected. There is controversy over budding nuclear powers like Iran and North Korea but also over whether the US plans to modernise its nuclear arsenal. Brian Barron travelled to the western state of Nevada, to visit the home of American nuclear weapons testing.
Radioactive fallout from the Nevada tests was detected in Europe 50 years later
The unlikely gateway to America's nuclear past is Las Vegas - the desert community just 60 miles from the Nevada test site.
I say "unlikely" because few today are aware that in the 50s and 60s - when Las Vegas itself was searching for its own road to riches, and casinos were not the money-for-old-rope, mega operations they are today - the city fathers cashed in on the seismic bangs that regularly broke their windows.
Unused to the first earthquake-like shockwaves, gamblers took cover beneath roulette tables when the chandeliers shook.
But soon motels were promoting the charms of rising at 5am and driving to the hills above Las Vegas, to see the horizon lit up by nuclear explosions above the test site.
Nightclubs offered atomic cocktails and toyshops sold ingenious laboratory games for eight-year-old weapons scientists of the future.
In those carefree days, little was admitted officially about the risks from radioactive dust and other contaminants.
American TV showed stirring footage of US soldiers climbing into trenches, stoically waiting for the nuclear blast wave.
But years later, it could prove fatal to have been down wind.
The other day the brand new Atomic Testing Museum opened its doors in Las Vegas.
The museum is run in conjunction with the Smithsonian Institution
One of its managers, a retired physicist with many explosions behind him, showed me a prize exhibit - a full size mock-up of a very large bomb with a nuclear warhead. It was the T61 - still in the US arsenal.
It is hard to imagine such openness with the British or French nuclear deterrents.
I left the staff at the museum pondering how to tempt more visitors away from the casino slot machines and into their eye-catching tableaux of the nuclear arms race and the doctrine of mutually assured destruction.
It's a great trip to the test site - past Sheep Mountain, the summit still dusted with snow, and then skirting a US military airbase at Indian Springs.
Our guide, from the nuclear security administration, pointed towards the runways and said:
"It's from here they control all unmanned missions over Iraq and Afghanistan. Inside you'll see pilots sitting at flight controls, manoeuvring their drones like the predator which can carry rockets and bombs."
To me it seemed like one of those American cultural junction points, where the precise reality of hi-tech weaponry and the billions invested in defence morph into Hollywood fantasies - like The X Files.
An hour after leaving Las Vegas, we were at the guard post outside Mercury - the nondescript town created to service the test site.
Large men in camouflage uniforms with holstered guns, all from a private security firm, checked credentials and made sure each of us was wearing a dose meter - a radiation sensor.
A national nuclear waste depository is planned for nearby Yucca Mountain
Soon we were driving through the hills, down into vast depressions with names like Yucca Flat and Frenchman Flat, dotted with the twisted steel remains of towers and other structures destroyed in nuclear experiments.
Tumbleweeds blew across the sandy soil. A jack rabbit, ears flapping, bounded over rusting railtracks that led to the nuclear rocket engines test plant - a relic from JFK's brief presidency over four decades ago and his generation's dream of reaching the stars under atomic propulsion.
It's over 40 years since the last atmospheric test in Nevada and 13 since the US (and other major nuclear powers) stopped underground tests.
But 1,000 feet beneath the desert, in a labyrinth of tunnels constantly swept by giant motorised vacuum cleaners - to protect laser devices from dust - weapon scientists conducted what are called "sub-critical tests" with plutonium and high explosives.
Their job is to ensure that America's ageing arsenal is safe and reliable.
At laboratories in New Mexico and California, other weapons experts have quietly begun to draw up new designs for replacement weapons.
But, barring a global crisis and total change of policy, the USA will never resume testing in Nevada, making do instead with simulations of nuclear explosions by super powerful computers.
So the riveting cold war archaeology of the desert test site, along with its herd of wild horses, rattlesnakes and bald eagles, could well open up to determined tour groups - if they can jump through the hoops of federal security clearance.
From Our Own Correspondent was broadcast on Saturday, 30 April, 2005 at 1130 BST on BBC Radio 4. Please check the programme schedules for World Service transmission times.