Between the shooting of Shinzo Abe with a homemade double barrel shotgun and a homemade bomb being used here, looks like all the laws in the world cannot stop a determined attacker. Japan's reputation as a "safe" country is largely artificial anyway. They have some pretty nasty serial killers and sex weirdos.
From what I've heard about Abe though, as well as being retired, he wasn't a bad guy, at least for a politician.