No, you have to assume that with Robertson's 25+ years of support for Israel (on theological and moral grounds), he sees a dire and predominating threat from Islamists, and he presumably he believes Giuliani may be capable of stopping that menace.
I'm neutral on G., but he is the only candidate whom I've ever heard directly addressing "The Big Lie" that Arab Muslims love to spout about "Palestine", Israel, and Jews.
And I don't mean "only candidate this election", I mean "only candidate, ever".
I think he sees a "spiritual soulmate" in Rudy.