Assassination as an act of war

I say this with weariness, but I really believe it. While I have nothing good to say, obviously, about ISIS or its leadership, I object, as a citizen of the United States, to assassination missions being carried out in my name without a declaration of war or immediate provocation. Assassination of foreign leaders or agents is a war crime absent a specific casus belli and state of war; even then it should only be carried out in specific circumstances where dire danger justifies it, not as a routine tactic. We need to foster the evolution of a world where war is not a first resort, and never launched as an initial aggression or for illegitimate purposes such as overthrow of foreign governments for ideological reasons or aggrandizement. Acts of war should be carried out only after deliberation of our lawmakers not our executives, except in cases of immediate attack or justified fear of immediate attack. If we would like other countries to adhere to a similar standard, we must uphold it ourselves. This is a critique of both parties and nearly all politicians, since there are very few who would actually uphold such principles even if they could. 

I have been called naive making this argument but I insist: if we want others to play by rules and take every possible measure to avoid armed conflict, we must do so ourselves. Since World War II, our policies have been very much in conflict with these principles, and I think many of our troubles as a nation arise more or less directly from that fact.