10 September 2014: The answer to this post's question is yes, based upon polling data of American citizens conducted recently. We nearly all believe that IS terrorists are already here in the USA. Well, if you live in Houston, Texas it's not a polling data issue based upon an unsubstantiated belief, it is a fact.
Above is an image of an Islamic State terrorist leaning on a counter at Jason's Deli in Houston. The IS jihadist logo is circled in red on the right shoulder of the jihadists covering Islamic robe. The Houston Police Department was called to investigate this male suspect. What they found in short order was an Islamic State jihadist wearing body armor underneath his appropriately black Islamic State robe.