Major Nidal Hasan
Major Nidal HasanReuters

The trial in the Fort Hood massacre in Texas, in the United States, opened Tuesday. Shooter Nidal Hasan immediately admitted to murdering 13 people, telling the court, “The evidence will clearly show that I am the shooter.”

Hasan, who is representing himself in court, went on to argue that he had done the right thing by opening fire on his colleagues at the Fort Hood army base.

“War is an ugly thing. Death, destruction and devastation are felt from both sides…  I was on the wrong side, but I switched to sides,” he said.

Evidence will show “that we are imperfect Muslims trying to establish the perfect religion,” he added.

Hasan began the 2009 attack by shouting “Allahu Akbar,” the Arabic phrase for “Allah is great.” He then fired repeatedly at the unarmed soldiers around him, stopping only when he was shot by officers responding to the attack.

The U.S. military decided to define the killings as a “workplace shooting incident” rather than terrorism.

Hasan has attempted to argue that the murders were “in defense of others” – those “others” being the Taliban terrorists who were at risk of dying at the hands of the U.S. soldiers he targeted. The judge has denied his efforts to use that defense.

Many of the dozens of people who were wounded in the attack will be taking the stand in upcoming days. They face being questioned by the man who shot them.