Theresa May says the March 4 attack on Sergei Skripal is a "flagrant breach of international law and the chemical weapons convention."

Would the (alleged) (attempted) Castro poisoning breach the same international law if carried out today (assuming the countries have ratified the relevant treaties)?

(One argument might be that the recent event involved a "military grade" substance, but it appears the law doesn't work that way.)


The chemical weapons convention entered into force in 1997, so the majority of attempts on Castro occurred before the Chemical weapons convention entered into force.

While assassination may sometimes be legal during a war, it is not legal outside of hostilities. One is allowed to kill enemy hostiles. One is allowed to use lethal force against someone who is threatening your country. But you can't kill someone who isn't an imminent threat

The assassination of Castro would be an extra-legal act, if it occurred outside of hostilities. And if the USA were defeated in war by a state friendly to Cuba, former presidents could be in trouble. However, the USA has the best-funded military in the world.

The chemical weapons treaties envisage the use of chemical weapons in war. There is not much if anything specifically about the use of chemical weapons in peacetime. It is not a radical interpretation of the convention that it doesn't intend to ban chemical weapons in war, but allow them in peace.

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    Although with any act involving multiple countries, the question is always "legal according to whom"? – origimbo Mar 17 '18 at 20:54
  • My question is whether this would be a breach if carried out today. (There were chemical weapons conventions back then. It could be another Question whether they were breached at that time.) – Keith McClary Mar 17 '18 at 20:54
  • I've extended slightly. Chemical weapons are not allowed in war, under the treaty. Assassination is not allowed, except as part of war, and then it is covered by the Geneva Conventions – James K Mar 17 '18 at 21:50
  • One definition of "extra-legal" is "(of an action or situation) beyond the authority of the law; not regulated by the law". The Question is about "international law and the chemical weapons convention". Are you saying that the Skripal poisoning would also be extra-legal, i.e., not a breach? – Keith McClary Mar 22 '18 at 17:02
  • I'm trying to avoid "illegal" which brings up questions of jurisdiction. Targeted assassinations of a national leader are an act of war, so would fall under the Geneva Conventions. Assination is generally not allowed under the Geneva Conventions. – James K Mar 22 '18 at 17:19

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