The situation in the middle east and northern Africa is not a case of identical rebellions against identical governments. Egypt's government is a corporate military government. Getting rid of Mubarak wasn't easy, but the essential government was left intact. There was no regionalism, no tribalism in the take over by the Free Officers movement in 1952. (General Naguib, the front man for the rebellion was Sudanese, and he was eventually ousted by Nassar, but otherwise, there were no tribal rivalries in the rebellion, which was a strictly an operation by the military.) Nassas was succeeded by Sadat, and Sadat by Mubarak because these officers had moved up through the government ranks. The ouster of Mubarak has left the Egyptian government intact.
Sadam Hussein al-Takriti was a tribal leader as well as an operative in the Ba'ath Arab Socialist Party, and he represented the dominant tribe around the city of Takrit. The Ba'athist were, however, a Sunni organization in a nation in which Sunnis were the minority. If we had enforced the 1991 no-fly zone in Iraq, and the Shi'ites had looked like beating Hussein, the Ba'athists would have dropped him like a hot rock, intent on assuring their survival as the Sunni-dominated political party.
Got-Daffy is also a minority tribal leader. However, there is no political structure in place such as was evident in the Egyptian Free Officers movement, or the Iraqi Ba'athists. The only "political party" is the apparatus which Got-Daffy has created to prop up his power. It's an all or nothing situation. If he is toppled, power will be up for grabs. As long as he looks like winning, many members of the military will probably continue to support him--but there's no reason to think they have a particular loyalty to him unless they are members of his tribe. I doubt that there is any love for the mercenaries he has bought. If it looks like he might lose, i believe a significant number of men in the armed forces may desert him, even if they don't actually turn their coats to support the rebellion.
Certainly there are no guarantees. But a successfully implemented no-fly zone could go a long way to toppling this piece of ****, who really only has power from the barrel of the guns he can hire. I say it's time to act.