Re: "environmental rights terrorists"
The legal definitions don't include intimidation.
USA (28 C.F.R. Section 0.85)
"the unlawful use of force and violence against persons or property to intimidate or coerce a government, the civilian population, or any segment thereof, in furtherance of political or social objectives"
UK Terrorism act 2006
"terrorism is a violent action that:
- Endangers a person’s life, other than that of the person committing the action
- Involves serious violence against a person
- Causes serious damage to property
- Creates a serious risk to the public’s health and safety
- Interferes with or seriously disrupts an electronic system"
Now the last two do apply to these jokers at Gatwick, but lets be clear, legally a terrorist must be involved in violence, damage or serious risk to safety.
Intimidation is it's own crime.