Answer :
William quotes the constitution in order to; explain that the ideas America is built on sometimes come with a cost.
Letter from a Union soldier analysis
According to paragraph 4 of the text which reads thus;
- I look at "We the people" differently now. We the people, in order to form a more perfect union, bled and died. We did this to establish justice.....
It follows from the excerpt that the intention for quoting the constitution is to; explain that the ideas America is built on sometimes come with a cost.
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