The world could end at any moment thanks to the countless number nukes out there. According to a 2010 Ploughshares Fund report, 22,000 active nuclear warheads are scattered around the globe. This means, one political conflict that keeps escalating could result in the end of modern civilization as we know it.
One nuclear blast followed by another and so on, has the potential to kill a great number of the worlds population. This scenario is particularly frightening when you take into account the number of countries that have nuclear capabilities, and are not in friendly unions with the United States.