set +H
The switch: turns history expansion off where it gets in the way.
This entire collection lives behind one character, and some people prefer their exclamation mark quiet — anyone who pastes commands with ! inside double quotes knows event not found.
set +H turns expansion off for the bash session; setopt nobanghist does the same in zsh. The relics stay in the museum — Ctrl+R and Alt+. don't depend on them.
$ echo "Atenção!"
bash: !": event not found
$ set +H
$ echo "Atenção!"
Atenção!