Hydrofracking is chemical terrorism.
Legalized, because the drillers have permits.
But if Osama bin Laden or some other villain bid on a lease in state land or found a willing private landowner, could Al Qaeda send in a drill team?
The intimidation part is that fracking steers American energy policy and the economy toward further use of fossil fuels at current consumption rates, away from a rapid and complete transition to renewables at a lower consumption rate.
The coercion is implied and stated threats of continued and worsening private and public poverty for noncompliance with the drill and burn regime.