Optional
All the folk asserting that you can stuff Mucho Stuff inside a laptop have something of a point, but there's another aspect that they're ignoring:
The US/MiddleEast ban impacts KINDLEs, too.
So some dimwit has decided that large phones (iPhone 7+ sort of thing) are OK, but Kindles are not OK. Oh, and battery packs are OK, as long as they're physically small.