Not in this case. The "Law of the Sea" isn't as open-slather as you suggest: there are International Laws and there are Antarctic Treaties in place and agreed between Nations. Japan's bogus "scientific" whaling activities in the Antarctic contravenes these.
Internationally-speaking, the Antarctic is a very special place, and it is protected by Treaty to prevent just this precise sort of exploitation.
See here for technical view on this.
> Where are the Indictments? When do the trials begin? Or are you countenancing vigilante justice?
The independent review that I have cited above suggests that Australia can and probably should take Japan to the international courts for "Law of the Sea" and "Antarctic Treaty" violations.
I concur with that view.
Failing that, I have no issues whatsoever with private citizens enforcing the established laws, as is their God-given entitlement to do. Private citizens have always enjoyed that right, going back to the Magna Carta and even before that. And they have had the right to perform Citizen's Arrests and to Use Force to give those arrests due and proper effect.
Doing *that* isn't "vigilante justice" — vigilantes make up their own laws and punishments as they go along.
In the Antactic, Japan is a rogue nation. They have no business violating the Antarctic Treaties and they ought to be stopped. Which is precisely what the Sea Shepherd Society is trying to do.
I say "Good on 'em".
Instead, they commit illegal acts themselves.
What is so good about your source? They are anti-drilling, climate change fanatics.