Jeff wrote:
Plugs and
receptacles are standardized, which makes almost certain the appliances
are properly connected. (In the UK it appears that appliances are sold
without a plug and rely on the consumer to do the right thing.)


Not so, it has been illegal to sell mains devices without an attached
plug for many years now in the UK. There is only 1 type of plug,
(excluding shavers sockets which are transformer isolated), which is
non-reversible and always has the provision for an earth (Not always
used with double insulated devices, but still the pin must be there,
sometimes in plastic). The sockets are shuttered to prevent accidental
'prodding' by little fingers.

Sure, and I think the plugs/sockets in use in the UK and those used
in the remainder of Europe are also much safer than the ones used
in the USA.
The USA types have the tendency to expose live pins when the plug is
partly removed, something that does not happen here.

"half the voltage" also doesn't matter much when the voltage is unsafe
to touch anyway. And it means "double the current" as well, which
increases the problem of overheating of bad contacts.

I'm sure the USA would go for a system like the European when it had
the chance to change. This is something that has been decided in the
past and is not so easy to change later, which is why it remains as it
is.