I agree with your statment but must point out: " Haven't heard of any Catholic homicide bombers." you forget the IRA.
This is however, why I believe the IRA has put down their weapons; not wanting to be associated with terrorists of the modern ilk.....
AFAIK, there were never actually IRA homicide bombers. They would plant bombs and such, but I don't think they ever (intentionally) blew themselves up.
No, I haven't forgotten the IRA. But they did not employ homicide bombers as a matter of course. When their bombs blew innocent people to bits, the perpetrators were well away from the carnage.They had NO interest in dying with their victims.
The homicide bomber is strictly a modern Palestinian/Muslim terrorist invention. I expect they'll continue to employ them as long as they have a steady supply of brainwashed fools eager to find Paradise with the aid of Semtex.