Reddit mentions of Green is the New Red: An Insider's Account of a Social Movement Under Siege

Read Green is the New Red if you want an account of the brainscrewery that is anti-animal activist rhetoric and legislation.

I recommend you read Will Potter's Green is the New Red for a detailed and sympathetic (since you posted to CMV) view on ELF.

To keep this short, I don't think it is appropriate for the government to conflate terrorism or violence with ELF actions which include sabotage and property destruction. Harm to buildings and equipment isn't exactly in the same moral category as harm to persons, although one could make the argument that arson poses a sufficiently significant risk to human safety that that distinction is blurred somewhat.

Also, Potter argues in his book that the reason for the terrorism label being applied to ELF activists is more motivated by the threat they pose to the profits of the firms they target than by an actual threat to public safety. He points out that right-wing hate groups who engage in violent acts against persons are not as great of a priority to the FBI.