Not necessarily. Buddhism has a military component (Zen Buddhism is closely tied to Bushido and the Japanese warrior mentality). It's not common, and Buddhism tends to be more peaceful than other religions, but there are exceptions which are condoned.
Originally Posted by Sonnabend
In "What Buddhist Believe
," the Venerable Dhammananda wrote,
"Buddhists should not be the aggressors even in protecting their religion or anything else. They must try their best to avoid any kind of violent act. Sometimes they may be forced to go to war by others who do not respect the concept of the brotherhood of humans as taught by the Buddha. They may be called upon to defend their country from external aggression, and as long as they have not renounced the worldly life, they are duty-bound to join in the struggle for peace and freedom. Under these circumstances, they cannot be blamed for becoming soldiers or being involved in defence. However, if everyone were to follow the advice of the Buddha, there would be no reason for war to take place in this world. It is the duty of every cultured person to find all possible ways and means to settle disputes in a peaceful manner, without declaring war to kill his or her fellow human beings."
Basically, Buddhism counsels peaceful coexistence, but not suicidal pacifism. And, of course a paranoid schizophrenic's interpretation of Buddhism is likely to contain some non-doctrinal ideas.