Modern Day Eunuchs
The fall of the Han dynasty in China can be linked to the rise of the power of eunuchs. Their status at court and access to the Emperor and his family gave them influence and power until the court was so corrupt that the dynasty collapsed. There was nothing special about the eunuchs that destroyed the Han, it was the incompetence of the Emperor in being swayed by their influence that caused disaster. Now, there is nothing inherently evil about eunuchs - but their goals are completely unconnected with the good of the country. They seek personal greed and power over what benefits the people in the long run. The ruler, on the other hand, is directly tied to the health of a state. What benefits the state, helps keep the ruler and his heirs in power, therefore the ruler has an incentive to better a state so that he may stay in power. For example, when there is famine, the populace is in a state of unrest, protests break out leading to revolts, internal insecurity gives foreign forces an easier time in unsettling the borders, such a situation gravely threatens the ruler's ability to stay in power. If the populace is prosperous, however, there is less unrest, less violence and the ruler has a stronger chance of staying in power. Therefore, the ruler's fate is tied to the strength of his state and visa versa. When the ruler starts listening to those who have no interest in maintaining the state, no interest in maintaining the power structure, the ruler's power is weakened and will eventually collapse.
Today there are modern day eunuchs(although these keep their balls), but influence the rulers in a similar way. The average lobbyist has a passing interest in governmental stability(because it will affect her or his client(s) profits) but is motivated primarily by personal interests. The fundamentalist loonies actively favour the collapse of the state hoping it will lead to the end of the world and heaven for them(genocide and torture for everyone else). Again these have no interest in the health of the state. When actors such as these are heard above those who have a stake in government, the government begins to decline. It is not necessary for a ruler to be altruistic in order to take actions to benefit the state, the ruler must be pragmatic because what is good for the country is good for the ruler. When those in government take a less pragmatic view, choosing short term profits and increases in power over long term power and stability they undermine the state and they undermine themselves and their institutions of governance. Like the last Emperors of the Han whose incompetence and greed was a spit in the face of the founders of the dynasty, so too the politicians who listen to modern-day eunuchs spit in the face of the founders of their governments.
History tends to repeat itself, the collapse of Han, the collapse of Rome, the collapse of the USSR were all tied to incompetent government and corruption, not outside forces. If democracies such as the United States fail, it will not be because of terrorists, it will be because of the modern-day eunuchs, the corruption that comes along with them and the politicians who place them above all else.