Not humanitarian, but a democracy among dictatorships.
And for strategic reasons. They are a buffer and they occupy
some of the Islamic hatred that would cause the varying factions to try to
wipe out each other (ex. the numerous Iran v. Iraq conflicts of the 1980's)
Israel helps deflect some of that, it could be a lot worse.

And they help with little projects like bombing Sadam's Nuclear power plant.
Just like they will if Iran gets to close. They take care of the dirty chores
for us.

One other huge thing. Intelligence. They have a very able intelligence
agency.