Amr Hamzawy, who'd been in the now-dissolved parliament, said action is needed to prevent more "suffering" under a president with "sweeping powers," as Egypt had for 60 years under men like Mubarak, Anwar Sadat and Gamal Nasser.
"Morsy is the ... president who has sweeping executive (power), sweeping legislative (power) and ... puts himself above the judicial branch of government," said Hamzawy, founder of Egypt's Freedom Party. "That is a very dangerous mix, which can only lead to a dictatorship."
The rest of the world is watching, too.
Former U.S. diplomat Jamie Rubin said Morsy's edict "brings to mind all the fears that people in that part of the world have had about the Muslim Brotherhood when it comes to democracy."
The unrest raises new concerns about stability in Egypt, which has gone through two years of protests and turmoil.
"The majority of the people are really suffering, and they were looking forward to some stability," said Radwan, the former finance minister, who served under Mubarak as well as in the government that followed him. "I'm afraid that this constitutional declaration has blown it up."