While that may be part of it, in my view the most fundamental reasons are twofold:
1. Israel is wealthy and prosperous and stable, and the Arab Muslim states that surround them are not. For leftists, this is a terrible crime as it "proves" that Israel is oppressing the Muslims. Remember, for liberals it's all about economics and class. Culture, religion and outlook have nothing to do with it.
2. Israel's best (and maybe only) ally is the United States. This makes them doubly guilty in the eyes of the left, because the United States is the single biggest problem in the world today, so our friends are automatically suspect.
On a side note, some of the worst, most blatantly biased reporting I have ever seen from CNN has come during this war. Hexbollah couldn't buy a better commercial. Perhaps the above points are driving this.
I can't get over CNN airing that fraud Robertson being led around by the nose by Hezballah... No, no terrorists here! He would have been a good visitor to Theriesenstadt too! And they aired it!