The origins of "You Worry Me" remain murky: it first appeared on the Internet in June 2002, but our attempts to verify whether its real author is an American Airlines pilot and/or someone named John Maniscalco have so far led only to dead ends.
According to the FAA Registry, John Maniscalco is indeed a real pilot, but this item was also printed in a less vitriolic form in the Hyattsville, Maryland, Gazette (under the title "An open letter to my Arab-Muslim neighbors") on 12 October 2001 and credited to a Kevin Daly of Beltsville.
Newspaper publication of a piece as a letter to the editor is not a reliable indicator of true authorship, however, as demonstrated by another widely-circulated Internet piece about President Clinton that was printed in several different newspapers under the names of at least four different people.
The Gazette letter might have been based on the Internet version, or the Internet version might be an altered transcription of the Gazette letter; John Maniscalco might have been the original author (or alterer), or he might have been someone whose name became attached to the piece simply because he forwarded it to others.
Aside from the question of authorship, this is not an item that can be branded "true" or "false," because it's merely someone's expression of his opinions. Thematically, it's a more overt expression of the feelings conveyed by such (apocryphal) September 11-related legends as the claim that no taxis were to be found around the World Trade Center the morning of the terrorist attacks: the fear and unease generated by the knowledge that the perpetrators were people who had been living among us undetected for months; people who, although they may have been foreigners, were not out of place amidst the cultural diversity of America. How, then, do we now distinguish friend from foe? Wouldn't it be so much easier if, as advocated in this essay, we could simply assume all ARAB-MUSLIMS to be guilty and demand them to demonstrate otherwise?
But such an approach is not only inimical to many of the principles American stands for, it is also logically flawed. What terrorists bent on the destruction of the U.S. would hesitate to camouflage themselves by hypocritically waving American flags or professing a false love for America? We cannot judge people by outward appearances alone, and that realization leaves us feeling scared and powerless.