Конвенция ООН по морскому праву содержит перечень таких случаев. Обсуждаемый казус под него не подпадает...
Как раз все подходит:
San Remo Manual on International Law Applicable to Armed Conflicts at Sea. Specifically, paragraph 67
67. Merchant vessels flying the flag of neutral States may not be attacked unless they:
a) are believed on reasonable grounds to be carrying contraband or breaching a blockade, and after prior warning they intentionally and clearly refuse to stop, or intentionally and clearly resist visit, search or capture;
b ) engage in belligerent acts on behalf of the enemy;
c) act as auxiliaries to the enemy s armed forces;
d) are incorporated into or assist the enemy s intelligence system;
e) sail under convoy of enemy warships or military aircraft; or
f) otherwise make an effective contribution to the enemy s military action, e.g., by carrying military materials, and it is not feasible for the attacking forces to first place passengers and crew in a place of safety. Unless circumstances do not permit, they are to be given a warning, so that they can re-route, off-load, or take other precautions
..Остальное, мне кажется, демагогия, попытка выкрутиться из ситуации...
Демагогия - представлять террористов и нацистов жертвами. В ответ на требование остановиться, они кричали в эфир "убирайтесь в Освенцим" и "мы поддерживаем арабов, помните об 11 сентября".