Sometimes Governments classify information for national security reasons. Or because releasing it publicly will put its spies at risk. Or cause a mass panic. This is in the panic category.

British nuclear weapons have been repeatedly dropped, struck by other weapons, and on one occasion carried on a truck that slid down a hill and toppled over

We're not talking about an oops, sorry, tripped and dropped the shopping. Nuclear friggin' weapons. I like this bit too:

Four of the incidents happened abroad, in Germany, Malta and near Hong Kong.

I flippin' live near Hong Kong. In it, actually. The rest of the article is just as scary. Take this:

the designs of Britain's early nuclear weapons, from the 1950s and 1960s, were unsafe and primitive, and that the MoD was "lucky" to have got away with not having more serious accidents, including nuclear explosions.

What really makes me pause for thought is there are the acknowledged nuclear powers: China, US, Russia, UK and France. Then there's the new nuclear powers, such as Israel, Pakistan, India, North Korea and Iran to name a few. So if the UK has had 20 accidents in 40 years, and being a first world country this can be taken a low estimate of what happens in each nuclear country...I think you get my drift. We shouldn't be worried about the nukes. We need to worry about the mechanics looking after these trucks.