In general, to be willing to govern, someone has to be more interested in retaining power and having control than of taking care of their citizens. Otherwise, leaders are "just people" with a charisma or commanding presence.
They propagate their beliefs further than the average person. Because of this, their prejudices and fallacies are also replicated among people. This includes publicly inflammatory comments, threats, and disrespect spawned, not by misunderstanding, but by outright hostile feelings towards others. Further, lack of patience, understanding, and tolerance leads to hostile, reactionary tactices when a perceived threat or disrespect is "committed".
The media of each country becomes skewed by their government. Even the US government routinely abridges the "freedom of the press" under the auspices of "national security".
The propaganda of government leaders, through popular media, supported by biased media executives and supporting journalists, are tools by the hostile egos mentioned above, used to pre-load skewed, false, and charged information. They trick their citizens into giving up their right and ability to decide for themselves.
Unfortunately, this is natural. Prejudice, deceit and power plays are natural tools of the human mind. As a species, we today are no different than those who founded civilizations around the world thousands of years ago. We are just lucky that we have survived to see and create such marvels of technology as we have today; however, it is inevitable that, eventually, we will devastate our civilizations and decimate our populations.