A Syrian boy and other victims of a chemical attack leave a hospital in Hatay, Turkey, before returning to Syria. (Ozan Kose/AFP/Getty Images)

Last week’s sarin attacks by the Syrian government against civilian targets in Khan Sheikhoun, and the subsequent U.S. retaliatory missile strikes against a Syrian air base, raise many new questions about Syria’s six-year civil war.

Much of this coverage has focused on implications for the future of U.S. policy. But there’s another big question: Why would Syrian President Bashar al-Assad use chemical weapons — and risk international condemnation and retaliation?

Assad has been the dominant force in the Syrian civil war, which has cost more than 400,000 Syrian lives. The opposition is increasingly fragmented and the Syrian government has for the most part held tightly to the reins of power using conventional weapons.

When the Assad regime deployed chemical weapons in 2013, the Obama administration unexpectedly held off from retaliating militarily, having failed to get congressional approval for military action. The decision to use chemical weapons last week generated pictures of dying children and international condemnation for the violations of international norms and law — along with U.S. military retaliation.

Why then use chemical weapons, and risk international condemnation and retaliatory strikes, when other equally effective military options were available?

Assad took a calculated risk

A recent New York Times article offers one answer cited by Syrian civilians and foreign experts alike. The regime took a calculated risk to demonstrate its own impunity and the West’s impotence, thereby demoralizing opposition forces. We agree. This episode vividly demonstrates a tactic autocratic governments often employ: the deliberate initiation and escalation of risky conflicts to demonstrate strength and shore up support.

This strategy often intentionally violates international law or norms — in this instance, the chemical weapons taboo. In a 2011 paper in the Quarterly Journal of Political Science (ungated version), we document a similar pattern with regard to human rights law, particularly the U.N. Convention Against Torture (CAT).

Our work dealt with a puzzling phenomenon first documented by other scholars: Autocrats with the worst human rights records appear to be among the most willing to sign human rights treaties. Typically, the opposite is true, and states sign treaties when they are already largely in compliance.

Staying in power is the goal

Our explanation for this behavior followed precisely the Assad regime’s logic today. Here’s how this plays out. Human rights conventions increase the legal and other liabilities of leaders found to be ordering torture and other forms of inhuman or degrading treatment. But leaders are only likely to pay these penalties once they are removed from office. Leaders willing to fight to the bitter end would find these risks minimal.

Similarly, violating the chemical weapons taboo opens a leader like Assad to greater risk of personal punishment after leaving office, and leaves Syria open to international retaliation in response to chemical attacks. To leaders who intend to cling to office, and who are confident in the ability of their regime to withstand external attack, such costs are of minimal concern.

Leaders in this position are extremely unlikely to relinquish power except by extreme force. Determined autocrats who are confident of their military position vis-à-vis their opponents may find the cost of military and economic international sanctions small. In fact, violations of international norms allow these leaders to credibly signal their resolve to stay in power — and put down the opposition.

Leaders who are less sure of their ability to hold on to power, in contrast, are hesitant to cross the line and violate international norms. These less-secure leaders are also more willing to negotiate with any emergent opposition.

Assad’s attacks, then, were designed to leave the opposition demoralized, with a sense that continued rebellion was futile and international support was lacking. Having withstood a U.S. attack and reveled in defiance, Assad may even find a boost in his popular support.

There may be domestic gains as well

Autocratic leaders — and the Assad regime in particular — don’t look to incite only international disputes to rally domestic support and to demoralize their opponents. Sometimes, they rely on domestic opponents to serve a similar end.

Many analysts, for instance, argue that Assad has for years been deliberately empowering, or at least avoiding direct conflict with, the Islamic State. This radical group instills fear among religious minorities and moderates, who then back the regime out of fear of the extreme alternative. Foreign powers hoping to see an end to the Syrian civil war out of humanitarian concerns, of course, are in a similar conundrum.

In a recent working paper co-authored with James Raymond Vreeland and inspired by a book by Milan W. Svolik, we show that using fear in this way is a common tool of autocrats. Leaders, we argue, may have an incentive to adopt policies that enable mass insurrection against the regime. Fear of the chaos that could erupt in the absence of leadership then turns would-be challengers from within the ruling elite into those who actually rally behind the regime.

What do these theories say about the recent U.S. missile strikes?

Perhaps, from Assad’s perspective, the chemical attacks were a calculated gamble gone wrong. Assad risked and experienced a U.S. military response — but after all, he escaped attack on previous occasions. The regime paid a relatively modest penalty for its actions: damage to the Shayrat Airfield and some, but not universal condemnation. Civilian and opposition forces have gained a morale boost.

But if, as U.S. officials suggest, the U.S. strike is a one-off event — and one that intentionally imposed only limited military costs — the effect may be quite different. While Assad runs an even greater risk from continuing to use chemical weapons, the threat of similar retaliation seems a cost he might be willing to bear.

If so, the signal he sends through the use of chemical weapons is all the more damning. Through continued defiance of international norms after the missile strike, the regime appears all the stronger, and the U.S. all the more impotent, than before. This means the Assad regime is likely to continue to risk international confrontation in a bid to shore up its domestic position.

James R. Hollyer is a Benjamin E. Lippincott Assistant Professor of Political Science at the University of Minnesota.

Peter Rosendorff is professor of politics at New York University. Follow him on Twitter @PeterRosendorff.