No it's not, at least where the UK and most other European nations are concerned:
Seriously, who gives a tinkers cuss about some scum who are quite prepared to kill innocent people going about their business. It's the fact that the fluffies have taken over that has allowed these gits to do what they do. Sink their ships but leave them floating for the bloody sharks... You haven't executed them, extradited then or any other such nonsense. Let them tell a 12' Oceanic White Tip or Tiger shark about their Human Bleeding Rights.