I would even argue that anything that enables broad-area targetting since the invention of the Maxim machine gun and artillery would qualify as a weapon of mass destruction. In an ideal world, the first machine gun or dynamite would've made everyone see war as a very bad resolution mechanism since the 19th century.
But here we are, so the game is to not make war much worse than it already is.
I would even argue that anything that enables broad-area targetting since the invention of the Maxim machine gun and artillery would qualify as a weapon of mass destruction. In an ideal world, the first machine gun or dynamite would've made everyone see war as a very bad resolution mechanism since the 19th century.
But here we are, so the game is to not make war much worse than it already is.