psql and regex not like

This statement runs great from the psql prompt. Does exactly what I want.
select datname from pg_database WHERE datname !~ 'template|postgres' ORDER
BY datname;

But it doesn't work so well from the bash prompt. Not escaping the "!"
generates a bunch of garbage, while escaping throws an sql syntax error.

psql -Xc "select datname from pg_database WHERE datname \!~
'template|postgres' ORDER BY datname;"
ERROR: syntax error at or near "\"

What's the magic syntax?

(Yes, I could create a view and then query the view, but I'm going to be
running this remotely against dozens of servers, so I don't want to have to
create dozens of views, then need to recreate them every time I want to
change the query.)

--
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!