Writing in August 1944, Reinhold Niebuhr declared: "When … optimism is not qualified to accord with the real and complex facts of human nature and history, there is always a danger that sentimentality will give way to despair and that a too consistent optimism will alternate with a too consistent pessimism." In the midst of the horrors of World War II, Niebuhr was talking about mode of thought in a modern democratic society. The key, according to him, was for liberal idealists to never underestimate the unwillingness of evil to give way to reason. Never has his point been of more value than today.

I awoke last week with the expected social media commentary on President Trump's cruise missile strike in Syria: "We are not the world's police," "Trump violated international law," "We need a full investigation before acting" and, perhaps most naively, "We need diplomacy, not military action." All of these sentiments, though virtuous and well-intentioned, are foolish, ill-advised, and belie the realities of the situation in Syria.

For nearly 100 years, the use of nerve agents such as sarin gas have been unequivocally banned under the terms of jus in bello; it is a crime in the conduct of war. The Syrian government's indiscriminate use of sarin gas on its own citizenry in August 2013 prompted the supposed removal of all of Bashar al-Assad's chemical weapons stockpiles. Under threat of credible force from the Obama administration, Russia stepped in as the guarantor of an agreement which would remove these weapons and destroy them outside of the region. That process was purportedly completed in late 2014.

With the recent attack in Khan Sheikhoun, Assad has not only violated the internationally recognized conduct of war once more, but shown that he has, in fact, not given up all of his chemical weapons stockpile or been forthright about facilities capable of producing such high-tech weaponry.

Assad's use of the technology should not come as a surprise, and only further reveals the lengths to which this two-bit dictator will go in order to cement his grip on power. Last week, U.S. Ambassador to the United Nations Nikki Haley publicly claimed that U.S. policy would no longer "sit and focus on getting Assad out." Presumably, such a dangerous statement paved the way for Assad's recent attack. However, of even graver concern is Assad's willingness to pursue such routes. Unmasking evil (for any unwilling to see clearly beforehand), Assad's recent actions show that sometimes a leader without an exit strategy will go to any lengths to solidify his hold on power.

Make no mistake, this is just one brutal aspect of the Assad regime. Piles of evidence demonstrate thousands of detainees tortured to death by security and intelligence agents, bombed out hospitals and schools, and routine murder, rape and disappearances. All of these acts, like deploying sarin, constitute war crimes. Assad, of course, denies all of this. But in striking the Russian-backed deal in 2013 to remove all of Syria's chemical weapons stockpiles, Assad both admitted to the existence of its chemical weapons and agreed to give up those capabilities. The fact that these chemical weapons still exist, and continue to be used, delegitimizes any credibility Assad or Russia possessed. Thus, the limited and narrow cruise missile strike on the Syrian air base from which Assad's government is suspected of launching the attacks is both legitimate and just. Moreover, it shows that the Trump administration's threat of force in light of breached international agreements is fully credible.

This is not to say the U.S. is without sin. Indeed, our history, like that of so many Western countries, is stained with past injustices that will undoubtedly hamper our conscience for years to come. But when leaders such as Assad act beyond the pale of common humanity, it is evident they are, as Niebuhr would term it, "children of darkness." We must recognize Assad for what he is, for as Niebuhr also said, "The preservation of a democratic civilization requires the wisdom of the serpent and the harmlessness of the dove." Given the political realities of our world, diplomacy can only take us so far with children of darkness like Assad. At some point, action is necessary.

Alexander Betley, of Northfield, is a student.