In his inaugural address Tuesday, Barack Obama called on Americans to remain hopeful of America's promise in the face of war and economic troubles and to set aside political differences, calling to mind Jefferson's words from the Declaration of Independence:  

"The time has come to reaffirm our enduring spirit; to choose our better history; to carry forward that precious gift, that noble idea, passed on from generation to generation: the God-given promise that all are equal, all are free and all deserve a chance to pursue their full measure of happiness."  

Read the entire text of Obama's speech: Inaugural Address