The US National Nuclear Security Agency has revealed that it plans to keep a small number of nuclear warheads actively maintained in order to defend the planet against giant asteroid strikes.
This astonishing revelation came to light after the Government Accountability Office did an examination into the NNSA's efforts to start dismantling the large majority of the US's old nuclear warheads that were built during the Cold War.
In its report the GAO found that rather than dismantling all of the weapons the NNSA had decided to keep a few 'on ice' until proper regulatory measures were put in place that would assure their maintenance in case of a possible 'extinction event' asteroid.
"While NNSA has declared these CSAs to be excess and, until March 2013, had scheduled them for disassembly beginning in fiscal year 2015, the national labs' retention letter has also characterized the CSA associated with this warhead as an "irreplaceable national asset." The WDD program is coordinating NNSA's evaluation of their use in planetary defense with the support of LLNL, LANL, and Y-12."
While the idea of keeping any nuclear weapons will always be a controversial issue, this may actually be one of the few situations where both sides can agree to their existence.
It's certainly true that it has been over 65 million years since the last asteroid of that size hit the Earth but the fact is there will be plenty of smaller but still potentially catastrophic asteroids that could in theory hit the planet.