The frustration comes against a backdrop of deep-rooted skepticism among pro-democracy activists that U.S. policies under President Obama will help transform the region, despite his vow to engage the Muslim world in a highly publicized speech here last month. Some view Obama’s response to Iran’s protests, muted until Tuesday, as a harbinger of U.S. attitudes toward their own efforts to reform their political systems. The Egyptian government, they note, is a key American ally, and U.S. pressure on Egypt for reforms began subsiding in the last years of the Bush administration.

“When Obama does not take a stance, the very next day these oppressive regimes will regard this as a signal. This is a test for his government,” said Ayman Nour, a noted Egyptian opposition politician who was recently released from jail. “If they can turn a blind eye to their enemy, they can turn a blind eye to any action here in Egypt.”…

On Wednesday, Fatah said he received a Facebook message announcing a protest in downtown Cairo the next day to support “democracy” in Iran and to mourn the death of Neda Agha Soltan, the young woman whose killing, captured on video, has become a global symbol of the Iranian uprising.

On Thursday, 10 large green trucks filled with riot police arrived at the meeting place. Not a single protester showed up.