The Department of State is in charge of all the embassies and consulates and are key in making policies when dealing with foreign countries and in ensuring the well-being of the United States and its citizens. The department is led by the Secretary of State who is chosen by the President and is a part of their cabinet.
Yes because a tyrant can and will do whatever he/she wants. I'd rather die than be under the control of a tyrant. In a democracy, I feel like my voice is heard (however small).