Perhaps Rosenthal though she was in like company - you know, the left wing "Israel is at fault" crowd present in some quarters of the Administration. Well, she let that presumption get her in trouble. The US has enough trouble earning credibility with Israel, so her remarks were deemed inappropriate and counter-productive.
Pakistan: Suicide bomber attacks tribal police, killing 4 (Reuters)
from the article: U.S. official's criticism of Israel ambassador sparks furor