Question

Read the excerpt from "Keynote Address.”

Of course, the war in Vietnam must be ended. But it must be ended, as President Johnson said last March, by patient political negotiation rather than through the victorious force of arms, even though this may be unpalatable for those raised in the tradition of glorious military victories. But like our other complex problems, this one must also be solved responsibly. Just as we shun irresponsible calls for total and devastating military victory, so must we guard against the illusion of an instant peace that has no chance of permanence.

How does the speaker develop ethos in this excerpt?

by citing President Johnson as a credible source
by comparing two different problems with similar resolutions
by using the language “guard against the illusion of an instant peace”
by demanding that the Vietnam war end

Answer 1

by citing President Johnson as a credible source

Referencing President Johnson lends authority to the speaker’s position and builds credibility (ethos) by aligning the argument with a respected public figure.