I wonder if the FBI looked into a liquid explosive on TWA Flight 800? Maybe this is why there was no explosive residue found.
The gov't searched about for any airport at which a bomb detection exercise had been run, got the name of the dog-handling agent and got him to claim he'd gotten the residue all over the place in an exercise he'd run.
Can you guess how many reporters talked to the agent? ZERO. Yep.
But one tenacious journalists poured through the documentation and discovered that indeed that agent HAD run such an exercise --on a DIFFERENT airliner.
I don't see where an explosives expert would be much of an expert if they only tested for nitrates.
My inclination has always been that someone on the ground crew planted an incindiary in or on the tank.