Iraqi civilians and U.S. soldiers pull down a statue of Saddam Hussein in downtown Baghdad Wednesday April 9, 2003. (AP/Jerome Delay)

Judging by recent headlines, this is not a good moment for democracy. The European Union, long held up as a model of democratic cooperation and consolidation, is threatened by the Greek debt crisis. Ukraine’s fragile democracy is under constant pressure from an increasingly autocratic Russia, and for better or worse the rest of the democratic community has proven reluctant to help. Iraq, the most prominent democratization project of the last decade, teeters on the brink of collapse with substantial portions of its territory controlled by militants.

We’re a long way from a decade ago, when serious people promoted democratization as a guiding principle for U.S. foreign policy—which culminated in the 2003 invasion of Iraq. As simplistic as some of those arguments seem now, it is worth remembering that they were fueled in part by bullishness among academics about democracy’s upside potential.

For example, in a 2008 CNN interview, then-Secretary of State Condoleeza Rice was asked if she regretted her role in the Iraq War—and responded with an emphatic “No.” She added, “I’m especially [proud], as a political scientist, not as Secretary of State, not as National Security Advisor, but as somebody who knows that structurally it matters that a geostrategically important country like Iraq is…under democratic leadership.” (We’ve added the emphasis.)

These ideas were not new. Politicians and scholars have long argued that democracies behave differently in international affairs. In general, research finds that democracies are more peaceful, credible, committed, and cooperative. But there is far less consensus on precisely why.

What makes democracies special?

What makes democracies special? Is there some positive universal property that follows automatically from elections and voting? If so, a policy of promoting democratization seems to make a lot of sense.

Or does the distinctiveness of democracies depend on some underlying characteristic that might not be equally shared among the very diverse set of states that nominally vest power in the people? If that’s the case, figuring out what that special characteristic is might help us understand why some democracies face periodic setbacks and failures or are more conflict prone than others.

In our new book War and Democratic Constraint, we argue that information is the key to popular constraint of democratic leaders. When it flows freely, citizens can hold their elected leaders to account, forcing them to hew more closely to public preferences. Without it, democratic leaders can start to behave more like autocrats–because citizens don’t have the information they need to hold them back.

But there’s a catch. Ours is an era of mass democracies in which millions hold the franchise—and it’s far from obvious that in that context information automatically flows freely between the highest elites and average voters.

The two key ingredients in democracy’s special sauce

We establish that two institutional conditions improve the effective flow of information and lead to more meaningful constraints on the foreign policies of elected leaders.

First, there must be an extensive and politically potent opposition that can blow the whistle when a leader missteps. Absent powerful opponents from multiple political parties, a leader can more easily keep quiet, obfuscate, or lie outright about failures or departures from public preferences.

Second, there must be strong and widely accessible media institutions that make it possible for the public to actually hear the whistleblowers.

Americans might imagine that both powerful opposition and widespread media access are universal to democracies. It’s not so.  One need look no further than the lead up to the Iraq War, to which most Democrats in Congress acquiesced, for an example of how hard it can be for the opposition in a two-party democracy to stand up to a determined chief executive. The news media’s institutional strength and public accessibility, in turn, vary widely among democratic states.

In other words, elections alone are not enough to deliver democracy’s hoped-for dividends. What democratization advocates seek will emerge only if a nation also possesses a particular constellation of democratic institutions.

We find that robust democratic institutions do constrain leaders in foreign policy, but that many — if not most — of the states that we think of as democracies do not have those institutions.  For instance, the United Kingdom, as a relatively low party democracy, doesn’t have an extensive opposition to push back against leadership. Democracies in southern Europe such as Spain tend to have much less widespread access to the media and less developed traditions of political non-interference in the media than do their northern counterparts.

A better way to promote democracy

When leaders misunderstand what aspects of democracy lead to peace, prosperity and international cooperation, they pursue policies that fail to deliver. Policies that encourage organic, domestically-driven democratization — for instance, through reforming the bureaucracy or empowering opposition parties and groups — may bear fruit over the long term. But imposing democracy is unlikely in the near- or medium-terms to produce states with meaningful popular constraints on foreign policy. In fact, imposing democracy may make some situations worse, as threatens to be the case in Iraq.

Nor should we expect the poorer and weakly institutionalized democracies that have emerged since World War II — such as those in Eastern Europe — to behave like their wealthier and more established counterparts.

Policymakers in advanced democracies like the United States and those in Western Europe would do well to devote fewer resources to increasing the number of the world’s democracies, and concentrate instead on helping democracies that already exist strengthen and respect the institutions that help information flow freely between elites and citizens.

Matthew A. Baum is Marvin Kalb Professor of Global Communications at the Harvard Kennedy School of Government. Philip B. K. Potter is assistant professor in the Woodrow Wilson Department of Politics at the University of Virginia.