History’s dictators, evil rulers, and terrorist chiefs all have one thing in common. They tell you what they plan to do before they do it.

There’s no better example than Adolph Hitler. In 1925, Hitler wrote a book called Mein Kampf in which he described his plan to mobilize Germany, conquer Europe, and exterminate Jews. He was laughed at. Ten years later he mobilized Germany, conquered Europe, and exterminated Jews just as he had promised.

Another example is Osama bin Laden. He declared war on the United States twice; once in 1996 and again in 1998. No one listened. He made clear his intention to attack the “far enemy” (understood to mean the United States). In fact, under Sharia, a Muslim is required to warn his enemy in advance of a coming attack in order to give the enemy one last chance to convert to Islam so his life may be spared. The Clinton and Bush administrations did not take bin Laden seriously until his 9/11 attacks that killed 2,996 people, and wounded more than 6,000 others in three states.

Now another enemy is giving fair warning. This article reports that North Korea has warned of its plan to detonate a hydrogen bomb in the atmosphere over the Pacific Ocean. At a minimum this would cause radiation poisoning and affect shipping below and planes in flight. Of course, the bigger threat is that this would confirm the existence or capacity to build an arsenal of nuclear-tipped ICBMs that could eventually kill more people than 9/11 and the Holocaust combined.

Is anyone listening? Stock markets definitely are not. Investors who ignore the clear warnings given by this latest enemy of civilization may learn the lessons of history the hard way.