What is the tone of Johnson's remarks at Gettysburg?

And what is an example of that

Johnson had a transformative tone. He really wanted to convey the idea of justice that afroamerican deserved. He tried to demostrate where his later administration might lead, which was to the legislation now known as the Civil Rights Ac of 1964.

An example of this:

"Their cause must be our cause too. Because it's not just Negroes, but really it's all of us who must overcome the crippling legacy of bigotry and injustice. And we shall overcome"