In a paper recently published in International Organization, we find a female president could face political pressure to act “tough” during international military crises and to adopt relatively hawkish foreign policies. That’s simply to combat the gender stereotype that women are less capable of handling foreign policy issues than men.

In September 2019, we fielded a survey experiment on a nationally representative sample of 2,342 Americans recruited through Time-Sharing Experiments for the Social Sciences (TESS). Our goal was to estimate two types of public opinion costs that scholars Joshua Kertzer and Ryan Brutger show can affect how leaders conduct foreign policy.

The first type are called “inconsistency costs.” These are the domestic political punishments leaders pay for making a threat against a foreign adversary and then subsequently backing down. For example, Barack Obama paid a political price for not enforcing his “red line” threat after Syria used chemical weapons. Higher inconsistency costs can affect foreign policy by giving presidents political incentives to actually carry out threats, even if doing so isn’t in the national interest.

The second type are called “belligerence costs.” These are the political punishments leaders incur for making threats in the first place. For example, voters largely disapproved of President Trump’s alarming threat to unleash “fire and fury” on North Korea, a nuclear-armed country. Higher belligerence costs — meaning leaders are punished more or rewarded less for making threats — can affect foreign policy by discouraging leaders from making threats in the first place.

... Here's what we found. ... In terms of disadvantages, higher inconsistency costs mean a female president will find it politically more difficult to back down from threats, which could make it harder to de-escalate crises. Lower belligerence costs also mean women have incentives to initiate conflicts.

However, there also potential advantages. If foreign leaders understand the domestic political incentives female leaders face, a female president’s threats will be more credible to foreign enemies, precisely because she is less likely to back down. This means women may actually be more effective at coercing foreign adversaries than men.

Many prominent scholars and policymakers believe more female leadership will lead to peace because women are biologically inclined toward peace and socialized to avoid aggression. Our research suggests more female leadership around the world could have a pacifying effect, but for a different reason. Enhanced threat credibility could allow female leaders to deter foreign countries from initiating disputes in the first place or compel foreign countries to back down once crises begin but before threats escalate to violence.

Research by political scientists Madison Schramm and Alexandra Stark finds, in the real world, female leaders are indeed under pressure to be hawkish to prove they’re tough and competent in foreign affairs.

Prominent female leaders like Margaret Thatcher from the United Kingdom, Golda Meir from Israel, Indira Gandhi from India, and Tansu Çiller from Turkey were often described as “iron ladies” because of their tough foreign policies. In the United States, high-ranking female foreign policymakers like Madeleine Albright, Jeane Kirkpatrick, Condoleezza Rice and Hillary Clinton often advocated more aggressive foreign policies than their male counterparts.

Of course, a President Harris — or any future female president — wouldn’t necessarily follow this pattern. But she would face different political incentives in national security crises than her male predecessors.