This is a no- win situation, I'd say.
On the one hand, it is a repulsive book that has enabled terrorists and terrorist wannabes such as the women arrested for the plot Thursday, puts people and property at risk, and has no place in civilized society.
On the other hand, it is technically protected by the First Amendment, partly because it doesn't specifically incite direct bombings and attacks, so sadly not much can be done about it.
It's the price of living in a free country.