Fuze is the universally accepted spelling for any explosive initiator in artillery, bomb or rocket ordnance and has been since the 1800s. It is the accepted NATO definition.
Fuse is an electrical safty device or pyrotechnic timing device, it is not a synonym. It is never used by manufacturers or military.
There is much confusion caused by Google autocomplete and autocorrect which does not recognise the difference.
OK, but you still defuse a bomb. Shouldn’t you defuze it?
A situation evolves slowly, so it is appropriate to defuse it like a slow burning pyrotechnic fuse.
A bomb has an instantaneous fuze (even if a delay is fitted) so it should be defuzed.
OK, that’s clear now, thanks.
Mercury fulminate vs. gunpowder-filled cord, right?
A good analogy.
Minor point: Mercury fulminate is very rarely used as a primary explosive. It has been superceded by Lead Azide, Lead styphanate and tartrazine.
Gunpowder impregnated cord is often referred to a Bicford Safety Fuse or its modern plastic coated type, Visco Fuse.
Thank you for offering me an opportunity to rekindle a little my dusty organic chemistry.
Er… speaking of minor points, I suppose that as an explosive primer you meant to mention
“tetrazene” 
, as “tartrazine” 
is actually a (nearly) harmless yellow food dye, and upon its chemical structure I doubt that it would even burn easily at room temperature (and if it did it would probably stink to high heaven) 
How embarrasing. Not only did I know that but I checked. Either old age or google being helpful. Either way Mea Culpa.
I will do better.
Ego te absolvo… 
Just pulling your leg - should I start enumerating my blunders I’d probably bore you to death 
Thanks for the clear explanation! It’s great to know the precise difference between “fuze” and “fuse.” Very helpful info!