The picture also clearly shows that the security person apprehending him has a gun holster strapped to his belt, but he doesn't seem to be wielding it (it could be in his left hand, which is behind the gunman's back, but the holster is on his right-hand side and his right hand is visibly empty). And it seems he's only trying to grab him, possibly to tackle him to the ground so he can't attack anyone else.

I don’t know what I expected but this man looks so normal.

The assassin is certainly considerate to wear a mask! It wouldn't do to get anyone sick while on a murder mission.

If everyone around you is wearing masks, not wearing a mask would stand out and attract the attention of security.

I know this is a joke, but if you want to get close to the target of assassination, you want to blend in with the crowd.

Also young! Throwing away one's life to murder a politician.

You are deceived by the fact that Japanese people aren't fully on the obesity bandwagon yet and plenty of them have teenager-like slim builds well into their 40s.

If you look at his hair, it is graying already quite a bit.

He's in his 40s and an ex-maritime self defense force member.

The man is in his life 40s sp certainly not young young

Wow! Well, I guess given Japan's life expectancy of 84, he's got half of his life still.

Life expectancy is counted from birth, not age 40.

That makes it even higher since infant mortality drags down the averages.

Your odds of making it to 84 only go up the older you get.