US Nuclear Explosions: a Thing of the Past?

Jeremy Bernstein, well-known author and former physicist, opines at the end of an article entitled "At Los Alamos: Learning to Love the Bomb", and appearing in the November 2013 issue of the American Physical Society News, that:

"The last above-ground nuclear test by the United States took place in 1962, ... . This is certainly a good thing. But I have only one misgiving. No one has seen a nuclear explosion in more than thirty years and the number of people who have ever seen one is dwindling. For most people, nuclear weapons are an abstraction. Perhaps there should be one more explosion in the desert of Nevada to remind us."

Now, this seems to me to be a truly bizarre suggestion! Perhaps Mr. Bernstein has been dithered by worry over the ongoing construction, in Iran, of the heavy water nuclear reactor at Arak, and the possible use by the Iranians of the plutonium which will be produced by this reactor, to build a nuclear weapon. Indeed, he has recently expressed his unease about the Arak reactor in an article in the New York Review of Books, dated 11 Nov 2013, and entitled "Iran's Plutonium Game."

Nevertheless, the idea of an above-ground nuclear explosion in Nevada, the purpose of which would be to "remind us" that nuclear weapons are not an abstraction: well, it just takes one's breath away.

Meanwhile, it seems to me that we might all be more concerned by the not remote possibility of an above-ground explosion of a nuclear weapon, within the borders of the United States, purposed by the agents of some adversarial nation-state or by an ad hoc group of self-appointed haters, and in the not so very distant future.