[paulific]

US jurisprudence may be different from the Australian law I studied, but as I understand it the "more likely than not" applies to the facts in a civil case not to the legal issue of what constitutes an act of war. That is a question of existing legal precedent and statute law. If there isn't a clear legal definition of cyber war they may indeed have a difficult time proving that cyber attacks are an act of war. But they may think it is worth the effort to try and establish a precedent.