To show the lunacy of security, I had my 1.8m Kensington cable taken by security and shipped with the checked in baggage and yet was allowed to take a 1.8m 13amp 3 core mains cable on board.
I think either would be equally effective for use as a garotte and the mains lead probably easier to use as it is more flexible, whilst very strong.
Although, as I have not had any thugee training, I can't be sure.
I also once had a 'security' person try to confiscate a roll of masking tape, because I might use it to tie up the crew.... you really couldn't make it up, could you?
That was another 'please get your supervisor' day and unsurprisingly I departed with my low strength tape.