How does the speaker develop ethos in this excerpt?

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.

1. Citing President Johnson: By referencing President Johnson's statement from last March, the speaker aligns themselves with a respected authority figure. This helps establish their credibility and expertise on the subject of ending the war in Vietnam.

2. Appealing to reason: The speaker argues for patient political negotiation instead of the use of force, even though it may be difficult for those who value military victories. By presenting a logical and reasoned approach, the speaker positions themselves as someone who carefully considers all perspectives and seeks responsible solutions.

3. Rejecting extremes: The speaker emphasizes the need to avoid irresponsible calls for total military victory and the illusion of instant peace. By acknowledging the complexity of the issue and advocating for a balanced approach, the speaker demonstrates their commitment to thoughtful and measured decision-making.

Through these rhetorical strategies, the speaker enhances their ethos by presenting themselves as knowledgeable, reasonable, and responsible in their approach to ending the war in Vietnam.