Final answer:
Protesting at Trump's rallies is legal as long as it is peaceful and lawful.
Step-by-step explanation:
Protesting at political rallies is generally protected by the First Amendment of the United States Constitution, which guarantees the freedom of speech and the right to peacefully assemble. As long as the protesters do not engage in violence or other unlawful activities, it would be legal for them to protest at President Trump's rallies. However, each state and local jurisdiction may have specific regulations or permit requirements for protests, so it is important for protesters to be aware of and comply with those rules.
Learn more about Protesting at political rallies