It is not unusual to see American flags flying in people's yards or on their houses, or fences. No holiday is required, to put out the Stars and Stripes. I see Texas state flags around, too, just haven't had a chance to get a photo of one yet.
On Cinco de Mayo, a controversy erupted in one of the Houston schools over the display of the Mexican flag. That controversy does not compare to the recent brutal beating of a child by his teacher, all caught on videophone. The video has "gone viral," as they say.