Since there is no chance anyone will do anything about it,  all we can do is act as silent witnesses to the slaughter.

New York Times:

Syrian opposition leaders raised the death toll to 260 in a military assault on Saturday on the ravaged central city of Homs, an attack that they described as the government's deadliest in the nearly 11-month-old uprising.

Reports were contradictory, given the difficulty of communications with Homs, and the Syrian government denied the death toll, calling it an attempt at propaganda ahead of a United Nations Security Council meeting on Saturday on Syria. But videos smuggled out of the city and reports by opposition activists showed a harrowing barrage of mortar shells and gunfire that left hundreds more wounded in the city.

"It's an unprecedented attack," said Mohammed Saleh, an opposition activist from Homs who recently fled to a nearby town to escape the mounting strife there.

As word spread of the barrage, opposition protests broke out on Saturday at Syrian embassies around the world, including in Egypt, Germany and Kuwait.

Accounts by activists, independently basing their information on what they described as contacts in Homs, said the barrage was apparently unleashed after defectors attacked two military checkpoints and kidnapped soldiers. One activist put the number of abducted soldiers at 13, another 19. They suggested that enraged commanders then ordered the assault, which lasted from about 9 p.m. Friday to 1 a.m. Saturday, focusing on the neighborhood of Khaldiya. Five other neighborhoods were also assaulted.

And then there's this eyewitness account:

"It's a real massacre in every sense of the word," said a resident in Khaldiya, who gave his name as Abu Jihad. "I saw bodies of women and children lying on roads beheaded. It's horrible and inhuman. It was a long night helping people get to hospitals."

Worldwide sanctions - treating Syria like a pariah nation - might have some effect. But that's not possible thanks to Russia and China who are blocking any concrete action by the Security Council.

As long as Assad has soldiers to carry out his orders to shoot to kill, the bloodletting will continue.