After a confidential email in which he called the Trump administration “clumsy and inept” was leaked, the UK ambassador to the US has resigned. Was it appropriate or inappropriate for him to resign?

After a confidential email in which he called the Trump administration “clumsy and inept” was leaked, the UK ambassador to the US has resigned. Was it appropriate or inappropriate for him to resign? Published on 10.07.2019 → Survey conducted on 10.07.2019 on 2700 U.S. adults