Why?
When the Israeli "art student/spy" story was first reported, person after person insisted all of them were Arab Isralis. Turns out they were not.
Then, as now, there was little to go on. But many were absolutely sure: 1. Nothing happened 2. Israeli Arabs did it.
Yes, I'm getting deja vu here.
Just like the five movers arrested in NJ after 'celebrating' WTC (last word from the Forward recently is that some were Mossad agents), the two movers and their female companion apprehended in PA (never any follow-up on this story), and the men with maps of nuclear power plants in a Midwest traffic stop (last word from Ashcroft was that this incident never happened), there is so much speculation here, stated as absolute certainty, that these Israelis must be Arab.