The next time you think one person cannot have a dramatic effect on mankind and the future, think about this:
A single German, Wilhelm Souchon, decided at the start of WWI that he was going to take his battleship, the Soeben, to Constantinople, which was then the capital of the Ottoman empire and Turkey. His purpose, with just his one battleship, was to cause Turkey, a very powerful country at the time, to enter the war on the side of Germany.
He was successful.
Because of this decision, Russia lost access to the Mediterranean sea and the British could not send supplies and reinforcements to Russia via the southern route. This basically meant Russia did not have an all-weather port with access to the rest of the world.
This was a big reason why Russia fell in WWI and lost the war to Germany, which led to the fall of the tsars and the rise of the Bolsheviks, which led directly to the rise of the Soviet Union. The Ottoman empire fell apart after WWI because they lost the war, and this resulted directly to the current situation today in the middle east with so many countries fighting each other. Most of the countries of the middle east, including Israel, Iraq and Iran were formed when Turkey lost the war.
All because one man had the audacity to think he could force the Turks to make a decision.
Sometimes these things boggle the mind.