In recent months, North Korea’s efforts to build and arm a nuclear-capable intercontinental ballistic missile have garnered significant attention, but it’s important to remember that Kim Jong-un isn’t the only nuclear player on the block.  Another nation the United States has found itself butting heads with increasing frequency already possesses a massive nuclear stockpile (the largest in the world, in fact) and announced plans last year to begin fielding a more modern ICBM of their own: Russia. Worse still, if you remove the United States from the list of countries that have their own nuclear arsenals, the U.S. currently has strained, or worse, relations with half of them.

America’s growing emphasis on reliable missile defense systems, then, makes perfect sense, but the ability to shoot down an offensive nuclear launch is only half of America’s deterrent strategy.  The other half, which dates back decades, is the concept of mutually assured destruction, or the promise that any nuclear attack would be met with an equivalent one, ensuring the utter destruction of all nations involved in a nuclear war.

The concept itself dates back to the 1870s, when English author Wilkie Collins wrote, “I begin to believe in only one civilizing influence—the discovery one of these days of a destructive agent so terrible that War shall mean annihilation and men’s fears will force them to keep the peace.”

To date, the United States has relied primarily on its stockpile of Minuteman III Intercontinental Ballistic Missiles, which have been operational since the 1970s.  These missiles, and the systems that operate them, are almost comically outdated, and often rely on the 5.25” floppy disks many readers may recall using to play “The Oregon Trail,” back when computers will little more than big, noisy calculators.