Last week commemorated 70 years since the atomic blasts at Hiroshima and Nagasaki that ended WWII. This week will recall Japan’s eventual surrender, as the Emperor overruled his governing military chiefs who wanted a national fight to the death. A dramatic and dignified ceremony two weeks later on the USS Missouri with General MacArthur presiding would conclude the most lethal calamity in human history, with over 50 million dead.

Commentary of the last week has focused on the morality of the U.S. atomic strikes on two Japanese cities. Defenders insist the strikes saved lives, while critics argue they were intrinsically immoral for killing over 140,000 Japanese, mostly civilians. Some critics claim Japan would have surrendered anyway, eventually, or that it was the Soviet declaration of war on Japan, in between Hiroshima and Nagasaki, that really persuaded Japan.

These revisionist claims aren’t persuasive. The Emperor in his surrender announcement specifically cited the bombs, not the Soviet attack on Japanese occupying troops in Manchuria. Japan’s ruling military council remained adamant against surrender, despite both the atomic blasts and the Soviets. They saw surrender as unacceptably dishonorable. The Japanese military still had millions under arms, still occupied much of East Asia in a vast empire, and could mobilize the whole nation to resist a U.S. invasion whose rivers of blood might compel America to negotiate peace.

Japan’s militarists were maybe also inspired by their ally Adolf Hitler’s refusal to surrender, also preferring national suicide, waiting until the advancing enemy was literally a few hundred yards from his Berlin bunker before committing his own suicide.

Although complicit in his nation’s wars of conquest and terror that had killed tens of millions, the Emperor at least cared more for his own people than did Hitler or Japan’s military dictatorship. The atomic blasts empowered his unprecedented intervention against the militarists, some of whom, as he expected, then tried to overthrow him.

Speculations about short term alternatives to ending the war are historically unpersuasive. Perhaps the most persuasive arguments against the atomic strikes are those that invoke the just war criterion, which prohibits intentionally targeting non-combatants. That’s an important debate, with serious thinkers on both sides. But we should be realistic about the likely outcome if the U.S. had not used atomic weapons.

Hiroshima and Nagasaki both had military facilities and industries, but of course U.S. military planners knew civilian casualties would be enormous, despite public warnings of impending attacks. Civilian casualties had been even greater under Allied conventional bombing of German and Japanese cities throughout the war. WWII was the first great modern war in which civilian deaths far outnumbered military deaths. This ratio, starkly at odds with Christian inspired just war teaching, resulted from the murderous, genocidal designs of both Germany and Japan, to which the Allies reacted with stern reciprocity. The stakes of WWII were not just strategic advantage but survival.

Allied decision makers in August 1945 were no longer worried about survival but they did want to end the war as quickly as possible. They had no desirable options, and so had to pick the least undesirable one. America had already lost over 100,000 men against Japan in four years, which is the equivalent of about 250,000 today as percentage of population. Losing perhaps another 100,000 or more to feed the perverted Japanese militarist dream of climactic battle on the Japanese mainland in which all 70 million Japanese would engage did not appeal to U.S. decision makers.

There were also the added moral considerations that Japan was prepared to execute several hundred thousand Allied prisoners, and that Japan’s wars of conquest in Asia were killing perhaps a quarter million Asians every month. China, the numerically largest Allied power, had already lost 20 million to Japan. Japan itself had lost about 3 million in its wars, to which hundreds of thousands, if not millions would be added, in a U.S. invasion, accompanied by ongoing conventional bombing, a starvation blockade against Japan, plus the added factor of Soviet war against Japan’s massive Manchurian force.

Critics, religious or otherwise, of the atomic attacks tend not to focus on the exponentially more deadly alternatives of continued war, whose chief victims would have been civilians, especially Chinese, Indonesian, Malaysian, Burmese and Vietnamese. Typically they pronounce such considerations utilitarian and/or consequentialist, and therefore morally and theologically unacceptable.

But this insistence on abstract doctrine over actual consequences makes their arguments mostly inconsequential to policy makers, whose chief focus must be consequence, not theory. Those who defend the theory need to accept that shunning the atomic weapon would have been worth the lives of, say, another half million Chinese children. That’s a hard bullet to bite for theoretical consistency.

Many critics of the atomic bomb also evince a uniquely American confidence in reasonable conclusions to nearly every human challenge, a propensity even more common now after 70 years of relative peace amid increased health and prosperity. Understanding radical Islam is hard now for intellectuals. Comprehending vastly more powerful and even more deadly genocidal regimes like the Third Reich or militarist Japan, which waged industrial level slaughter based on deep mystical/ideological commitments, is nearly impossible for those of us who don’t have to make hard choices in which civilizations hang in the balance.

Few now alive can recall when America, 75 years ago, was a third rate, semi-isolationist military power better known for refrigerators and Hollywood than for strategic reach. By August 1945 the U.S. by enormous and historically unprecedented exertions had become a global power. But even then it could not without the slaughter of its own men, and countless others, easily subdue a still great and potent empire whose rulers favored national suicide over defeat. The atomic weapons, produced by the leading lights of Western science before the Axis powers could craft their own for more nefarious purposes, offered the least horrible option. U.S. policy makers achieved a decisive end to history’s worst war, the orderly surrender of a murderous regime, the miraculous creation of a democratic and prosperous Japan, and 70 years of approximate global peace.

We don’t like to admit to the complexity and frequent horror of a fallen world where even relatively decent rulers must confront abhorrent and irreconcilable powers with less than desirable means. But if government by consent is to survive the future, as it barely survived 75 years ago, moral and theological thinking will have to defend the approximate good against swelling evils with the always flawed political and military instruments at hand.