@Sherri_Ingrey @Caleb James DeLisle A lot of it is based on fear and migration trends. That fear is exploited in older conservatives who view Israel as a symbol of stability and responsibility vs the chaos of the third world and global south.
Fear of terrorism is a big thing and that has traditionally been associated with Islam.
Much of it has been carried out by "Islamists" who have little in common with the 3 billion or so Muslims in the world, but majority of such conservatives don't analyse that deep.