On Takuya Kimura's radio program Kimura Takuya no What's UP SMAP!, he was asked by a listener, "Why do you wear your watch on your right wrist?", to which he replied, "I'm also wearing it on my right wrist now, why are you wondering about that?".
Kimura then proceeded to explain, "Wearing the watch on the right wrist is a symbol of peace". It apparently refers to when a sniper is aiming for his target, he keeps his right hand's index finger on the trigger while checking the time on the watch on the inner side of his left wrist. But if the sniper were to wear his watch on his right hand, he'd have to let go of the trigger momentarily in order to check the time, which will prevent him from firing the rifle.
Kimura has always been wearing his watch on his right wrist but became more conscious of it after learning about its significance to a sniper. But he says that there are still times where he wears it on his left in dramas to match the other actors.
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