05/07/2013 09:56 am ET Updated Jul 07, 2013

Do Red Lines on WMDs Matter?

Do red lines matter? There has been mounting criticism of the Obama administration for setting a line in the sand on Syria -- the movement or use of chemical weapons -- and then apparently failing to act out on its promise. The criticism has come in two varieties: First, those like John McCain say the line was a dumb idea because it basically hands Assad a blank check to do anything else short of using chemical weapons, including mass indiscriminate attacks against civilians, target mosques and minarets, and displace millions of Syrians. Along this line of criticism, the red line feels arbitrary and strange, since the killing of more than 70,000 Syrians would seem to be a graver violation of international humanitarian norms than the use of chemical weapons. Moreover, the previous use of such weapons in the region -- Saddam's gassing of the Kurds in Halabja in 1988 barely warranted a peep out of Washington at the time (in fact, we were complicit in giving Iraq relevant equipment, arms and intelligence support that abetted the attacks).

Chemical weapons, of course, have been around since the Peloponnesian War, when sulfur was used to burn down cities. The Brits proposed burning sulfur during the Crimean War in hopes the winds would help them gas Russian troops at Sebastopol. And both Germans and British employed chlorine and mustard gas during the First World War. Interestingly, during the Second World War, shortly after the Italians sprayed mustard gas against the Ethiopians in 1936 and the Japanese fired gas-filled shells at the Chinese, forcing their retreat in 1941, FDR issued a direct warning to the Japanese and Germans not to use chemical weapons. And his threat worked (Obama should reread his World War II history).

A second line of criticism stems from international relations literature on reputation costs. If a leader draws a line in the sand and then fails to follow through on his threat, presumably others will think he is weak and thus be less likely to be deterred from making future provocations. In Arms and Influence, Thomas Schelling argues that a state's reputation for resolve "is one of the few things worth fighting over." It affects our future ability to credibly deter aggression and it hurts our relationships with and promises made to our allies. Not everyone agrees with this line of logic. Daryl Press, for instance, believes that power is what matters to make threats credible, not a state's past actions. Jonathan Mercer also discounts the importance of reputation and resolve during foreign crises. In other words, threats are situational, and so Obama's backing down on Syria would not signal to the Iranians that he is weak and unwilling to enforce red lines drawn.

I disagree with this logic. On Syria, if the United States does not either intervene or escalate the pressure, the message is clear: First, we are helpless to do anything, so dictators, go nuts. Second, if you have weapons of mass destruction, you have a blanket of immunity from outside intervention, so be sure to rearm those chemical, biological and nuclear stockpiles. Finally, on Iran -- any red line we draw in the sign is basically just suggestive. Go on spinning those centrifuges because we really don't mean what we say. Obama should either a) not draw red lines or make promises he has no intention of keeping; or b) follow through on his ultimatum, by gradually tightening the noose around Assad, which could see fence-sitters among the Syrian population such as the Christians and Kurds switch sides, create dissension within Assad's inner circle, and weaken the more extremist elements within the opposition. Presumably a more engaged U.S. will strengthen secular groups within the opposition, by diverting funds and arms away from the Al-Nusra Front.

To be sure, a U.S.- or NATO-led intervention is not some panacea that will paper over all the sectarian grievances, personal feuds or other triggers for postwar violence in Syria. It will hasten the fall of the regime, but not guarantee a smooth aftermath. In fact, it could easily portend a messier post-Assad Syria, simply because it will leave in placed several armed actors whose relative power will be left unclear, tipping the scales toward those who are best organized and most willing to use violence, which in this case are Islamist parties (there's a reason why the Bolsheviks took power after Russia's civil war).

Even still, a democratic Syria run by Islamists is preferable to both the status quo of civil war or a return to a Baathist dictatorship at peace with its neighbors. The likelihood of a secular democrat coming to power are virtually nil. If that is the lofty expectation of U.S. senators pushing Obama to intervene, then we should stay out. We should intervene because it will save lives, improve our standing in the region and our ability to project power and dictate events, and weaken Iran (though a Sunni-led Syria does not necessarily guarantee it will join the Saudi-led bloc against Iran given how the region's dynamics make for strange bedfellows, but presumably it will weaken ties with Tehran, which helps our leverage during nuclear negotiations).

Assad has destroyed the minaret of a UNESCO-protected mosque in Aleppo (and one of the most gorgeous places of worship I've visited in the region), he has allegedly used chemical weapons against his own people. The question then becomes: What more would he have to do to warrant an international response?