And then there's the check that's done on all bottles taken airside for sale to the public.
I have observed the channel that the pallets go through, at a number of airports. A quick glance at a full pallet, evidently to check that the packaging is undisturbed, and "OK, mate".
Noting that hi-jacks in the early 1970's (one example of many; VC10 at DXB) were in some cases planned 12-18 months in advance and used staff infiltrated into airside jobs over a longer period, the complacency of the security authorities who believe that it cannot happen again, while they persist in the absurd security theatre in the passenger, staff and crew channels, beggars belief.
Do they really believe that terrorist planners are incapable of co-ordinating a packer in the supplier's premises, a security guard, and an airside employee, to put explosives and/or weapons into the hands of a suicidal "clean skin" terrorist buying stuff in WH Smith? Perhaps all from the same ethnic background, in the UK at least.
I suspect, on the available evidence, that they do indeed believe that.
I think about this every time I watch some bored, officious, super-sensitive security person bullying a hard-of-hearing granny who did not realise she had to remove all her outer garments, metallic items, shoes etc to walk through a scanner and be patted down by a short-tempered wardress before being allowed airside, to prove that she's not carrying in her handbag or about her person the wherewithal to take control of a large civil aircraft.
Having observed these failings, how about solutions? Should they be more strict with these grannies?