Most Important Presidential Words

On Presidents' Day, let's think about what Presidents of the United States have said.  Perhaps the most powerful part of the position is an informal power, the bully pulpit.  When presidents speak, we listen.  What are the most important presidential utterances?  The easy ones are:

Washington's farewell address, by stepping down when he could have consolidated power and made himself a king, instead he established the nation as a democracy that puts laws above rulers.

Lincoln's Gettysburg address.  Enough said.

Eisenhower's farewell address in which he warns us of the rising power of the military-industrial complex

Kennedy's inaugural speech -- ask not...

Others?