本文以原爆的道德爭議為題，以美國思想家華瑟（Michael Walzer)和羅爾斯（John Rawls)作為主要探討對象，分析其立基於 義戰道德之原爆批判；並從「亞洲平民」的視角對其進行商榷，進而 提出另一種可能的思考途徑。華瑟和羅爾斯表示：明知會造成大規模 平民死傷的戰爭手段，只有在「極度危急」情況下方可動用，但就美 日之間的太平洋戰爭來說，美國從不曾陷入此種境地；再從罪行的輕 重程度來看，日軍不可與納粹相提並論，因而美國不該要求日本無條 件投降；因此，以屠殺平民的原子彈迫使日本無條件投降，嚴重違反 了義戰道德之基本原則。和華瑟、羅爾斯一樣，本文反對以這種或那 種國家理由去「合理化」蓄意屠殺平民的戰爭手段；但另一方面，卻 也無法完全同意華瑟和羅爾斯的所有論點，因其輕忽了亞洲平民的道 德份量，忽視了「制止極嚴重的人道災難」乃義戰道德所規定之重要 義務。本文申論指出：今日觀之，「不投原子彈」作為一種選擇，也 有其重大的道德損失；因其（以今日的後見之明）相當於選擇了「在 日軍已造成的上千萬平民死難之外，還將有數十萬或更多亞洲平民喪 生」之後果。

John Rawls criticizes Truman’s atomic bomb decision as a very grave moral wrong, while Michael Walzer denies the legitimacy of the atomic bombings as well as the US policy of unconditional surrender. According to Walzer and Rawls, weapons of mass destruction that would knowingly cause a huge number of civilian deaths could only be used under the exceptional condition of “supreme emergency”. Given that no “supreme emergency” occurred, or was ever likely to occur, throughout the Pacific War, Truman’s atomic choice was almost an absolute wrong judged in terms of just war morality. Or so it is interpreted by Walzer and Rawls. This paper argues, however, that Walzer and Rawls underestimate the very scale and severity of the humanitarian disaster in wartime Asia, the latter being caused chiefly by the war crimes of the Japanese army. To the extent that Walzer and Rawls discount the moral weight of the obligation to stop that humanitarian catastrophe, their total denunciation of the atomic bombings appears to be rather one-sided. The choice not to drop the atomic bombs, so to speak, could not have been made without incurring great moral losses, either. For it would have amounted to letting die another half a million or even more Asian civilians before Japan surrendered. This is not to say that Truman’s atomic decision
was therefore morally right. Far from it. Neither the decision to, nor the
decision not to, drop the atomic bombs could ever be fully legitimized as “the morally perfect choice” under the moral circumstances then obtaining.