How does Minerva cause harm to others in In the Time of the Butterflies?
Minerva's strong-willed defiance of Trujillo is, no doubt, admirable, but it does endanger her family. She is such as inspiration to her sisters that they all willingly join the resistance, but those actions put them at great risk from the dangerous and threatening Trujillo. She is transporting weapons, and her younger sister joins in that activity. She is exercising some passive resistance with her behavior in the prison (her making friends and educating the other inmates and passively just "going with the program"), but it is her younger sister who is tortured and who loses her baby. She is the known leader of the resistance, and her whole family is spied on and lives under the implied threat of Trujillo's men who literally stand guard outside their home. In the end, three of the four sisters is killed in an assassination plot. They all made their choices and seem proud of their role as the "miraposa" but they probably wouldn't have been involved in any active resistance if it weren't for Minerva. That said, I think it would be a mistake to blame Minerva for the deaths and heartache of those around her. The whole point of the novel is the willing sacrifice of those involved for the greater good, and the deaths of Mate, Patria, and Minerva prove that.
It is fascinating to examine how each of the four sisters responds to the terror of the Trujillo regime. Minerva, out of all of them, is the first to be involved in the rebel movement, thanks to her friendship with Virgilio Morales. Part of her character is her headstrong defiance of Trujillo's regime, and the way that she is able to face Trujillo without yielding. Note how she refuses to give in to Trujillo's sexual advances and then how she challenges Trujillo and gambles for the right to study law. Clearly, as it says in the text, she sets herself in opposition to Trujillo:
I look down at the lopsided scales as he puts his dice back. For a moment, I imagine them evenly balanced, his will on one side, mine of the other.
As her mother has already noted, Minerva is determined to "fight everyone's fight," even though this endangers the situation and lives of her family and those nearest and dearest to her. Unfortunately, although she did not desire it, part of being a rebel is the way that your actions endanger those around you, and thus Minerva does cause harm to others through her rebel associations.