Assad is retaliating against Syrians after contact with U.N. monitors.

Al-Assad won't stop. He is a minority ethnicity in Syria so that may be driving him somewhat. He is a member of the Alwite sect, a branch of the Shia religion. The Alwite sect is based primarily in Syria.
Syria is a country of about 20 million people.  I think Assad is driven by the fact his ethnic religion is a sincere minority in Syria, holds power over Sunnis, has a history geological right to Syria and its leadership. If he steps down he will be surrendering his identity and the future of what he views his ethnic domination.
Syrian ethnicity is constituted with 90.3% Arabs with minority groups of Kurds, Armenians, Turcomans, and Assyrians making up the remaining 9.7 percent of the population. Sectarian differences occur with Sunni Muslims (about 74 percent), Alawites (a Shi'ite subsect), Druze (a Middle-Eastern sect with a doctrine combining different Islamic, Jewish, and Christian elements), and other Muslim sects (about 16 percent). The Christian population in Syria (about 10 percent), and Jews number only a few thousand.
Former Secretary Annan wants 300 monitors. It would perhaps help, but, the approach has to be as much strategic to separate the people from the Syrian military as possible. In other words, the Syrian military has to leave the area where the monitors are and have been. The towns and cities will have to be left with local authority to maintain order as a method to have Assad's forces stand down. I think we are looking at instilling a police state enforced from internal organization other than Assad's forces. If a foreign power enters Syria there will be full blown war as Assad is just that desperate regarding his own 'kingdom.' Empowering local authorities to sustain their own peace while the Syria military rolls back into their official bases is a way to stopping this disaster in leadership. 
The Syrian military will have to be displaced into their own military bases by internal law enforcement structure organized at the local level. Basically, law enforcement that won't kill their own citizens. I think Assad is fanatical and there is nothing that will end that so long as his military remains in control by him. I would think there should be an ethnic mix in the Syrian military that might be harnessed through its generals to end the violence. The UN is walking on egg shells.
Syrian protesters gather around U.N. monitors during the monitors' visit to Duma, near Damascus.(Associated Press / April 23, 2012)
By Los Angeles Times Staff

April 25, 2012, 12:01 a.m.

BEIRUT — The presence of United Nations-backed monitors (click here) in Syria is providing only brief respites from violence and in some cases may be making the situation worse, a spokesman for U.N. and Arab League special envoy Kofi Annan said Tuesday.

Annan spokesman Ahmad Fawzi said the small advance team of monitors is facing great difficulty in stemming the fighting between forces loyal to President Bashar Assad and opposition groups.

"When they leave, the exchanges start again," Fawzi told U.N. Television in Geneva, referring to the monitors. "We have credible reports that … these people who approach the observers may be approached by security forces or Syrian army and harassed or arrested or even worse, perhaps killed."

Annan, meanwhile, reportedly told the U.N. Security Council that the situation in Syria was bleak and called for the deployment of the full 300-member monitor force authorized by the council to verify what is happening there. The monitors are part of a peace plan set up to end the fighting in Syria....