The same reason USA is subsidizing half the middle eastern countries - its a strategic location near extremely important transit routes, near important resources, and right between major powers so the region doesn't squarely fall in any major power's sphere of influence and thus up to be influenced.
I dont know why all these conspiracy theories think the usa<->israel relationship is so strange, but dont blink at the relationship usa has with egypt, uae, saudi arabia, bharain, etc.