First and foremost, terrorists should be treated the same way as the other people. What they do is another question. Evaluation of their deeds is all in hands of the authorities. In case one talks about treating the terrorists for what they have done in terms of choosing the way to make them responsible for their actions, the approach as to the war enemies is more applicable.
First off, terrorists act, ignoring the laws of certain countries and the entire world. Naturally, applying the laws of the peace time to them, i.e. treating them as regular criminals would be ridiculous, since they commit crimes that do not fall under almost any laws or regulations of the majority of countries of the world. So far, as most terrorists come from the Middle East or Arabic nations, it is extremely common that they explain the cause of their attacks as the “Sacred war”. This way they involve the third parties, i.e. the peaceful countries, in the unilateral war. The question of why do they have to be treated as some regular criminals, therefore, arises. Based on the actions of the terrorists, the return reaction of the authorities should be based on the same principles. If the terrorists show no grace to the innocent victims of their acts of violence, there is no need for the country to show any consent to them.
Furthermore, most terrorists act the way they want so far, as they almost never get a full-scale punishment for what they have done. Pacifists and legal counselors protect the terrorists, claiming that they have the right to be tried as the rest of the criminals. If the terrorists knew that they would undergo severe punishment, sometimes maybe even illegal, they would think twice before committing any terrorist act, no matter whether it is an airplane hijacking or undermining of a huge building with thousands of innocent people inside.
Terrorists have to be afraid of the punishment, dictated by the law of war, not the civil regulations. Keeping such individuals in fear for their lives and freedom may be the only way possible to save thousands or millions of other innocent people’s lives. The acts of terrorism should be punished even in spite of violation of human rights and laws.