Final answer:
The excerpt utilizes parallelism to emphasize escalating frustration and the need for a change in tactics due to the perceived futility of previous efforts.
Explanation:
Parallelism is the rhetorical device used in the excerpt. It draws attention to the many peaceful steps the colonists have taken, reflecting the repeated attempts made before resorting to more drastic measures.
In the text, the speaker questions the effectiveness of various approaches, highlighting the lack of progress and the exhaustion of options, ultimately leading to the consideration of different strategies.
This rhetorical device serves to emphasize the escalating frustration and the need for a change in tactics due to the perceived futility of previous efforts.
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