Political leaders are as vulnerable to narcissism – self-obsession and a need for admiration – as the rest of us, and it can have grim side-effects, a study has shown.
Research of the 19 US Presidents who served between 1897 and 2009 found that those who scored highly for narcissism spent more time at war.
The reason for this is that the presidents wanted to look heroic and strong, and remain at war even when no longer necessary, scientists believe.
The eight leaders who scored above average on narcissism spent an average of 613 days at war – compared to 136 days for the 11 presidents who were below average on narcissism, the study found.
Lead researcher John P Harden, a doctoral student in political science at the Ohio State University, said, "More narcissistic presidents tend to only exit wars if they can say they won, and they will extend wars to find a way to declare some kind of victory.
"They want to look heroic and strong and competent – even if it means fighting the war beyond what is reasonable."
Previous research by Harden found that the most narcissistic presidents preferred to instigate conflicts with other great power countries without seeking support from allies.
Harden studied presidents from 1897 – roughly the time the US became a great power in the world – up to George W Bush's exit from the White House in 2009.
In order to measure presidential narcissism, Harden used a dataset from 2000 created by three researchers to assess the personalities of presidents.
These researchers gauged narcissism using the expertise of presidential historians and other experts who had written at least one book on a president. Each expert completed a personality inventory with more than 200 questions about the president they studied.
Based on these results, Lyndon Johnson was the president who scored highest on narcissism, followed by Teddy Roosevelt and then Richard Nixon.
The president who scored lowest on narcissism was William McKinley, followed by William Howard Taft and Calvin Coolidge.
The US was involved in 11 wars during the period studied.
Results showed that presidents who scored low on narcissism, such as McKinley and Dwight Eisenhower, "separated their personal interests from state interests, saw war as a last resort and pursued speedy exits," Harden said.
Meanwhile, Franklin Roosevelt and Nixon, who scored high on narcissism, "had difficulty separating their own needs from state interests" and were involved in lengthy wars, he said.
Of course, many factors determine if the US goes to war and how long wars last, Harden said. But this study showed presidential narcissism is one key factor – one that has been overlooked in previous studies.
"What I found is that the traditional way political scientists have looked at war dynamics doesn't capture the whole story," he said.
"Presidents don't always look rationally at the evidence to make their wartime decisions. Many presidents have done that, but others are more interested in their own self-interest than the interest of the state."
There are several evidence-based reasons why narcissistic presidents should experience longer wars, besides their focus on their own personal interests, Harden said.
One is that narcissists have grander war aims – they have higher expectations because of their aggressiveness and belief in their own abilities.
"They also adopt ineffective strategies because of their overconfidence about their own abilities and the conflicting goals that arise from trying to maintain their self-image," Harden said.
"Narcissistic presidents spend more time worrying about their image than other presidents.
"These motivations, especially their desire to protect their inflated self-image, cause them to drag out wars longer than needed."
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