Phylactery mistook as a bomb. (tefillin)

Paranoia, 9-11 attacks, hijack.. and numerous airplane attacks are some of the reason US citizens are afraid of.

Phylactery (tefillin), Greek term for tefillin, leather boxes worn on the arm and head during certain Jewish services tefillin. Tefillin are two small black boxes with black straps attached to them; Jewish men are required to place one box on their head and tie the other one on their arm each weekday morning. Tefillin are biblical in origin, and are commanded within the context of several laws outlining a Jew's relationship to God. "And you shall love the Lord your God with all your heart, with all your soul, and with all your might. Take to heart these instructions with which I charge you this day. Impress them upon your children. Recite them when you stay at home and when you are away, when you lie down and when you get up. Bind them as a sign on your hand and let them serve as a frontlet between your eyes" (Deuteronomy 6:5-8).

The text that is inserted inside the two boxes of Tefillin is hand-written by a scribe, and consists of the four sets of biblical verses in which Tefillin are commanded (Exodus 13:1-10, 11-16; Deuteronomy 6:4-9, 11:13-21). Because each pair of Tefillin is hand-written and hand-crafted, it is relatively expensive, and a well-made pair costs several hundred dollars.

The word Tefillin is commonly translated as "phylacteries," though the Hebrew term is more often used. I have never met a Jew who puts on Tefillin who calls them "phylacteries."

Putting on Tefillin is the first mitzvah assumed by a Jewish male upon his Bar Mitzvah. Usually, boys are trained to start wearing them one to two months before their thirteenth Hebrew birthday. During the training period, boys don Tefillin, but do not recite a blessing. Subsequent to the Bar Mitzvah, a specific blessing, "Blessed are You, Lord our God, King of the universe, who has sanctified us with His commandments and commanded us to put on Tefillin, " is recited whenever they are worn. Many Jews say an additional blessing and prayer upon putting on Tefillin.

Tefillin are worn each weekday morning, but not on the Sabbath or on most Jewish holidays. On the fast day of Tisha Be'Av, and on that day only, they are put on during the afternoon instead of the morning service.

Source: http://www.jewishvirtuallibrary.org/jsource/Judaism/tefillin.html