Final answer:
The 1st Amendment guarantees the right to write newsletters that criticize the government.
Step-by-step explanation:
The amendment that guarantees the right to write newsletters that criticize the government is the 1st Amendment. The 1st Amendment of the United States Constitution protects the freedom of speech, which includes the freedom to express opinions and criticize the government without fear of retaliation. This amendment is an essential component of the democratic principles upon which the United States was founded.
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