An Obama campaign ban on green clothing during the candidate’s visits to Israel and Jordan has created wide puzzlement among observers of the Middle East.

In a memo to reporters, described as “a few guidelines we sent staff before departure to the Middle East,” Obama advance staffer Peter Newell laid out rules on attire for Jordan and Israel.

First among them: “Do not wear green.”

An Obama aide explained to reporters that green is the color associated with the militant Palestinian group Hamas. But while the color does appear on Hamas banners, there is no particular symbolism to wearing green clothes, experts said.

Moreover, green is more generally seen as a symbol of Islam.

“A ban on wearing green seems bizarre,” said Richard Bulliet, a professor of Middle Eastern history at Columbia University, who said the color is associated with the family of the Prophet Mohammed.

“I would hazard the guess that the campaign’s concern is more with distorted—and religiously inaccurate—reporting by Obama’s detractors than with any actual signal that might be conveyed,” he said, referring to false rumors that Obama is a Muslim. “You don’t want to have some blogger come along and say ‘Obama is showing his true color.’”

“I think they’re just being overcautious to a ridiculous degree,” Bulliet said.