The rally 'round the flag effect (or syndrome) is a concept used in political science and international relations to explain increased short-run popular support of the President of the United States during periods of international crisis or war. Because rally 'round The Flag effect can reduce criticism of governmental policies, it can be seen as a factor of diversionary foreign policy.
Political scientist John Mueller suggested the effect in 1970, in a landmark paper called "Presidential Popularity from Truman to Johnson". He defined it as coming from an event with three qualities:
In addition, Mueller created five categories of rallies. These categories are considered dated by modern political scientists, as they rely heavily on Cold War events. Mueller's five categories are:
Since Mueller's original theories, two schools of thought have emerged to explain the causes of the effect. The first, "The Patriotism School of Thought" holds that in times of crisis, the American public sees the President as the embodiment of national unity. The second, "The Opinion Leadership School" believes that the rally emerges from a lack of criticism from members of the opposition party, most often in the United States Congress. If opposition party members appear to support the president, the media has no conflict to report, thus it appears to the public that all is well with the performance of the president. The two theories have both been criticized, but it is generally accepted that the Patriotism School of thought is better to explain causes of rallies, while the Opinion Leadership School of thought is better to explain duration of rallies. It is also believed that the lower the presidential approval rating before the crisis, the larger the increase will be in terms of percentage points because it leaves the president more room for improvement. For example, Franklin Roosevelt only had a 12% increase in approval from 72% to 84% following the Attack on Pearl Harbor, whereas George W. Bush had a 39% increase from 51% to 90% following the September 11 attacks.