The nice thing about a transatlantic tunnel is that crustecaeans can be bought off cheaply
The various environmental organizations aren't going to be bought off cheaply.
If you get the sierra club complaining publicly about the tunnel, you instantly have about half of the politicians in the country in favor of it.
Plus any operation at this scale will require all the security if not more of a normal one. It is just too big not to be a target for someone.
