Incidentally, I don't know about the situation in the US, but in the UK this is one of the key rationales for this kind of action. Since it is a defence to argue that your actions were motivated by the need to prevent a greater crime, this kind of action potentially presents an opportunity to raise the legality of the state's nuclear weapons policy in court. As the article says:
> The U.S. Attorney’s office filed a document they called “Motion to Preclude Defendants from Introducing Evidence in Support of Certain Justification Defenses.” In this motion, the U.S. asked the court to bar the peace protestors from being allowed to put on any evidence regarding the illegality of nuclear weapons, the immorality of nuclear weapons, international law, or religious, moral or political beliefs regarding nuclear weapons, the Nuremberg principles developed after WWII, First Amendment protections, necessity or US policy regarding nuclear weapons.
> The U.S. Attorney’s office filed a document they called “Motion to Preclude Defendants from Introducing Evidence in Support of Certain Justification Defenses.” In this motion, the U.S. asked the court to bar the peace protestors from being allowed to put on any evidence regarding the illegality of nuclear weapons, the immorality of nuclear weapons, international law, or religious, moral or political beliefs regarding nuclear weapons, the Nuremberg principles developed after WWII, First Amendment protections, necessity or US policy regarding nuclear weapons.