That was an email to her, not hers to him. He was giving her the "lay of the land" at that time - basically, what the Israelis were going to do against a person who was going to be appointed to a job. He gave her suggestions to thwart that. We don't know if she did it or not and if she did, it is what she should have done if the president's appointment was going to fought against by a "country", any country.
If another president, let's say Trump, was going to appoint someone to a job and a country was going to try to cause that person not to be appointed, and the Sec. of State told Trump that was going to happen and told him how to avoid it, he would do it.