I had a thought on the way to church today. Perhaps monarchy has given way to democracy simply because of the political confusion that surrounds the death of increasingly vulnerable monarchs. Geneological monarchies always had problems with succession and murder plots. If you did not like the current monarch, you could stab or poison him or her with almost certain knowledge of who would next ascend to the throne. This sort of certainty only encourages regicide. Long range weapons makes that possibility a near certainty.
Democracy provides a very stable government that is less prone to revolution. Then I started thinking, you know if the public is armed with rifles, no monarch is truly safe and the government is always in jeopardy. It used to be that the king's wine steward could prevent poisoning and body guards could protect the royal person for swords and daggers. But with the advent of high powered rifles and other high-tech weapons, every public appearance of the monarch runs the risk of a revolution.
Perhaps the vulnerability of the monarch in the face of technology has caused the natural move to a democratic and decentralized system of government. Thoughts?