Answer:
Martin Luther King Jr. was a leader in the Civil Rights Movement for the African-American. He said this quote above mentioned in the question because he wanted the public to listen to his speech as he stands there as a religious figure who is trustworthy, respected. He uses an example of ethos to convince people for the cause.
1. The engineers made pontoons so that they could easily cross rivers.
2. They dug beneath the enemy's city walls to weaken them.
3. Used battering rams to hammered the enemy city's gates.
Most of just the common average citizens. You see, after WW1, reparations were high in Germany. Inflation rose and people were getting desperate for food and work. When the great depression hit, it hit Germany the hardest. The average German person was driven towards Hitler and the nazi party as Hitler said the Germans were not to blame and that he would fix all of their problems.
The one characteristic of command economy is that the individual pursuit of wealth is replaced by a concerted effort from all economic channels to improve society as a whole.