[MileHi]

Trump opines that the planes had bombs, needed them to get through the outside of the building.

They did, full tanks of avgas.

[xone]

of avgas

Jet fuel.

[Cboldt]

Technically, the avgas was just mass, contributing to inertia, to get the planes through the outer wall. Only the dense parts of the planes reliably got all the way through the building, hitting the first wall likely shredded the skin and much of the bodywork.

How can a piece of straw penetrate a telephone pole? Velocity! Impact!

Rods from God act like explosive, so do asteroids, but no "bomb" in those object.