Commander in Chief
The president.
He was the 18th President of the United States.
At the end of the US Civil War, General in Chief US Grant remained in that position. Later, President Andrew Johnson appointed US Grant to the position of secretary of war. Grant remained in that position until he was elected to the US presidency.
The President is in charge of the US, It is the most important position in the world.
The President Pro Tempora
President Pro Tempore
President Pro Tempore
President of the Senate
Franklin Pierce, 14th US President. Franklin Delano Roosevelt, 32nd US President. - Benjamin Franklin is commonly confused as a US President, though he never held the position.
There is no such position as Mayor of the United States (US). A Mayor is typically a political position for cities and towns. The United States is led by a president. Currently, the president is Barack Obama.
In the US, the President is the highest position possible in the government (and by default the highest position in the army). However, internationally there is no rank amongst people of any kind.
He was a US Senator.