Corrected entry: The crystal set in the kid's trumpet is never discovered or spoken about. Though it isn't set off by the boy's playing it during the State of the Union address, it remains in the trumpet and we are left to believe that the boy who likes to play his trumpet at both school and home will set off the crystal and blow himself - and likely a large number of others - up.
Brad
3rd Oct 2008
Correction: The crystal was set in Rachel's necklace. The detonator was set in Sam's trumpet. The bomb would only detonate if Sam played it while in the same room with the crystal, which is exactly what happened.
Brad ★
Doesn't really answer their question. Rachel still - probably - has the necklace, and the kid still has the trumpet. So unless Jerry figures it out and tells her to get rid of the necklace, it can still detonate I mean he will probably play at home - where the necklace is.