History Shows Attack on Americans in Libya Could Spur Rally Effect

Most domestic and international events, no matter how tragic, are subject to being swept up in the maw of the heated, no-holds-barred presidential campaign we are in now. Both campaigns' war rooms are constantly adjusting and readjusting their positionings, reactions, public statements, and actions relating to almost anything that becomes an issue in the news.

The killing of four American diplomats, including U.S. Ambassador Christopher Stevens, in Libya late Tuesday, is no exception. Republican nominee Mitt Romney and his advisers made the decision to use the attack as an opportunity to criticize President Barack Obama, and Obama's campaign representativeshot back that the campaign was "shocked" at the politicization.

Whatever the merits of the intense back and forth over the deaths of four Americans, we know from history that high profile international events in which the U.S. is involved or in which the U.S. is threatened can result in what is called a "rally effect," the result of which has historically been an increase in the sitting president's job approval rating.

The most substantial effect in Gallup polling history came after the terrorist attacks of Sept. 11, 2001, in which President George W. Bush's job approval rating rose by 35 percentage points. Other examples of the impact of rally effects in history include the initiation of the first Persian Gulf War in Iraq in 1991, when President George H.W. Bush's job approval rose by 20 points; the Cuban missile crisis in 1962, when President John F. Kennedy's job approval rose by 13 points; the capture of the merchant ship Mayaguez and subsequent rescue attempts in 1975, after which President Gerald Ford's job approval rating went up by 11 points; the killing of Marines in Beirut in 1983 when President Ronald Reagan's job approval rating increased by 4 points; and the death of Osama bin Laden in 2011, when Obama's job approval rating rose by 7 points.

It is difficult to quantify the exact determinants of a rally effect and its size. One key issue is the degree to which the American public is tuned into an incident and the other is the nature of the incident itself.

The killing of the four Americans in Libya generally fits the historical description of the types of events that precipitate rally effects -- given that it represents a direct attack on Americans and American interests. Thus, my initial hypothesis would be that this event could result in a rally effect for President Obama.

We are, however, in an unusual political situation now, as Obama is in the middle of a continuation of a separate rally effect that resulted from the Democratic National Convention last week. Obama's job approval rating, which had been as low as 43% in Gallup's Aug. 30-Sept.1 report, is now at 51% for Sunday, Monday, and Tuesday of this week. It is thus unclear whether or not there can be an additional rally effect manifested in his approval rating when it is already high, relatively speaking. Obama's approval rating is now, in fact, within two points of where it was as a result of a previous rally event -- the killing of Osama bin Laden in May 2011, when it reached 53%.

The Romney campaign is no doubt making very careful decisions on how their candidate should continue to react to the incident in the days ahead. What Romney will continue to say about the incident and what the impact of his statements will be is unknown at this point.

A commander in chief does not have to engage in highly successful efforts to be subject to an uptick in his job approval ratings as a result of a rally event. The idea behind a rally event is that Americans rally around their commander in chief as they come together in times of external events of significant note. The fact that there was a five-point rally effect for John F. Kennedy after the botched Bay of Pigs invasion in 1961 shows that the effect can occur even when those in charge were involved in creating the negative outcome.

The ultimate impact of the tragic incident in Libya on U.S. domestic politics, if any, is still an empirical issue that we won't have the answer to for days yet. In part, this depends not only on the level of attention Americans are paying to the incident and how it plays out, but also on any actions that the Obama administration may take in retaliation. More will be known by the weekend.