You'd have to transmit it before the client can double-spend, yes, but my point is that it's not necessary for the owner of the coins to have an internet connection.

You can receive incoming blocks on the Bitcoin network via satellite, radio etc. I doubt a government would be able to keep up the whack-a-mole game against many activists who can set up mobile block relays.

You can also send transactions over any communication, even SMS. A good example from Andreas Antonopoulos is that emoticons are a 128 character set, so you could send a 250 byte bitcoin transaction as a sequence of 15 emoticons.

Good luck stopping that.

Time-locked transactions can kind of help here.