magine you had a weapon so powerful that just testing it put your own side at risk. What would you do? The answer, as we know, is that you would set it off anyway - just to be sure.
Which is pretty much how it was when the nuclear arms race was at its height and the human race was in danger of not making it to the finishing line. For many years, both sides in the Cold War detonated warheads on remote islands, beneath the ocean and deep underground. With an apparent disregard for the effects on the planet, they even set off bombs above our atmosphere. In 1962, US tests high over the Pacific produced such spectacular light shows that hotels in Hawaii advertised rooftop "rainbow bomb parties". Unfortunately, they also knocked out street lights, televisions, radios and burglar alarms.
But in 1964, an explosion in the Van Allen belts had even more worrying consequences. The Van Allen belts are areas of charged particles that surround the upper atmosphere, and the intention was to "pump up" their radiation levels with a view to putting Soviet satellites out of action.
In fact the 50 kiloton weapon that was detonated at a height of between 300 and 400 miles did more than that. First, the radiation disabled both Soviet and US satellites. And, even more alarmingly, it then refused to go away.
It had been expected that the blast would make the belts a no-go area for a couple of days. But as the days turned into weeks and the weeks into months, and still no electronic equipment could pass through unscathed, panic began to spread through the military and space establishment. The belts, it seemed, had been poisoned for ever, and the space race was off until further notice.
In the event, the crisis lasted for well over a year, after which, it was business as usual. Except that an awful truth was beginning to dawn. As one military space expert put it later, "there isn't anything you do to the enemy that you don't end up doing to yourself".