Killing yourself in the process of killing your enemy is hardly a new thing. Samson's death has generally been regarded as heroic rather than insane. Perhaps it was both.

Suicide bombing is a horrible thing, which erupted in reprisal for some horrible things (done in reprisal for othe rhorrible things...etc etc), and it has been used to justify other horrible things in reprisal. The whole cycle of violence is insane.