The UK’s Telegraph reports (“Christmas truce of 1914 was broken when German snipers killed two British soldiers,” December 22) the incident, pieced together from historical records. On the front lines in France, British sentry Percy Huggins was felled by a German sniper; his platoon leader Tom Gregory retaliated against that sniper, only to be outgunned by another.

This may not fit the sentimentalized image of the truce, but taking it off such a pedestal makes it relevant to our messy world. Bertrand Russell noted that to “admit in theory that there are occasions when it is proper to fight, and in practice that these occasions are rare” yields far less war in practice than to “hold in theory that there are no occasions when it is proper to fight and in practice that such occasions are very frequent.”

The truce’s breakdown in this case remained an isolated flashpoint; it held on both sides, as close as under a mile away. The influence of an “incredibly professional” duty-bound Guards Brigade kept local tensions high from the beginning, with immediate rejection of Germans’ bid for a cease-fire.

Also instructive is the clear tit-for-tat aspect, driven by retaliation for specific aggressions rather than by general warlikeness. (One sniper indicating more made a third death inevitable.) Something needs to tip the balance to make hostility spread faster than toleration. That something, in one word: Politics.

Emma Goldman contended that without the socialist movement’s turn away from direct action and toward a reliance on political means, “the great catastrophe would have been impossible. In Germany the party counted twelve million adherents. What a power to prevent the declaration of hostilities! But for a quarter of a century the Marxists had trained the workers in obedience and patriotism, trained them to rely on parliamentary activity and, particularly, to trust their socialist leaders blindly. And now most of those leaders had joined hands with the Kaiser … Instead of declaring the general strike and thus paralysing war preparations, they had voted the Government money for slaughter.” And only the tripwire pitting of national leaders against each other could turn the assassination of an archduke into a feud that would multiply the tripling of Huggins’s death five-million-fold.

In his final letter, Huggins told his family: “I long for the day when this terrible conflict will be ended. You consider war a terrible thing but imagination cannot reach far enough for the horrors of warfare that can be seen on the battlefield are indescribable and I pray this may be the last war that will ever be.” A century of advance in global communications and commerce gives today’s Hugginses ample basis to coexist without politicians and the means to verify trust. It should not take another century to reach “the last war that will ever be.”

Carl Sagan is not usually remembered as a political prophet, aside from pioneering recognition of the dangers of nuclear war and remaining an inspiration to opponents of drug criminalization. But his inquiry probed any political order’s taboo “set of forbidden possibilities, which its citizenry and adherents must not at any cost be permitted to think seriously about” (like the USSR’s “capitalism, God, and the surrender of national sovereignty” or the USA’s “socialism, atheism, and the surrender of national sovereignty”). Otherwise, it would wither, as with antiquity’s Alexandrians who never “seriously challenged the political, economic and religious assumptions of their society. The permanence of the stars was questioned; the justice of slavery was not.”

While not a radical leftist like his feminist wife and coauthor Ann Druyan or his New Leftist friend Saul Landau (who, in a sign of the up-in-the-air alliances of the times, contributed to the Cato Institute’s Inquiry Magazine), his liberalism was influenced by the ferment of SDS’s participatory democracy Whole Earth Catalog-style emancipatory technology. It was thus steadfastly in favor of civil liberties, people power, and sexual liberation, and highly wary of moral panics and calls to trade freedoms for security. Despite being vilified by a right dominated by National Review hawkishness, he sought common ground with pro-lifers. As he said of Albert Einstein, he “was always to detest rigid disciplinarians, in education, in science, and in politics,” and his distrust of politics was evident in proposing “[a] series in which we relive the media and the public falling hook, line and sinker for a coordinated government lie.”

He took note that the flowering of inquisitive, tolerant values in ancient Greece and Renaissance Holland grew from their trading economies; as his muse Bertrand Russell put it,

The relation of buyer and seller is one of negotiation between two parties who are both free; it is most profitable when the buyer or seller is able to understand the point of view of the other party. There is, of course, imperialistic commerce, where men are forced to buy at the point of the sword; but this is not the kind that generates Liberal philosophies, which have flourished best in trading cities that have wealth without much military strength.

His antidote for the existential crises of nuclear war and environmental damage was not consensus reasonable-centrism — he was apprehensive of the triumphalist The End of History prediction “that political life on Earth is about to settle into some rock-stable liberal democratic world government” — but the widest possible experimentation. He recommended two of the great science fiction depictions of functional stateless societies: The Moon is a Harsh Mistress, with its “useful suggestions… for making a revolution in a computerized technological society,” and Eric Frank Russell’s “conceivable alternative economic systems or the great efficiency of a unified passive resistance to an occupying power.” He hoped the inspiration of such ideas would make a reality “the beginning, much more than the end, of history.”