Two years ago today, the revolution in Syria was sparked by residents of a small farming town called Dara’a who took to the streets after local schoolchildren were reportedly tortured by Syrian secret police for scribbling anti-government graffiti.

“It led to a major demonstration that was put down brutally by force, with the killing of several civilians,” Middle East scholar Murhaf Jouejati explained in our film The Regime, an excerpt of which is embedded above. “And it snowballed from there.”

The conflict today has become a bloody nationwide civil war with no end in sight, and the numbers are stark. More than 70,000 Syrians have died, according to UN estimates last month, and some experts warn the numbers could be even higher.  One million Syrian refugees are being assisted by the UN. Two million children face malnutrition, disease and severe trauma, according to a report released by Save the Children earlier this week.

As the fighting rages on, the international community continues to debate whether to arm the opposition forces with the antitank and antiaircraft weapons they say they need to sustain the fight.

France and Britain support ending a European Union arms embargo at the end of this month. “We cannot allow a people to be massacred by a regime that for now does not want a political transition,” French President François Hollande told reporters as he arrived in Brussels for a European summit meeting yesterday.

President Obama has steadfastly opposed arming Syrian rebels out of concern that the weapons could fall into wrong hands, such as jihadist groups on the ground. But in a shift from earlier policy, the U.S. announced last month that it will provide direct assistance to the rebels, including 200,000 ready-to-eat meals for members of the Free Syrian Army and assistance with education and sanitation services in rebel-controlled areas.

Meanwhile, concerns grow about the increasingly sectarian nature of the conflict, which pits the country’s Sunni Arab majority against its Alawite minority, which is disproportionately represented in the government.

Last month a UN panel accused both sides of committing massacres of civilians and combatants in an “increasingly sectarian” conflict, and warned that “the destructive dynamics of the civil war not only have an impact on the civilian population but are also tearing apart the country’s complex social fabric, jeopardizing future generations and undermining peace and security in the entire region.”

Next month, in Syria Behind the Lines, FRONTLINE will journey into that civil war to document for the first time the realities of everyday life for rebels, government soldiers and the civilians who support them on both sides.

For five weeks in October and November 2012, filmmaker Olly Lambert crisscrossed the Orontes River valley in Idlib province, a once-peaceful area in Syria’s heartland that is now a perilous sectarian front line. On one side of the river, the rebel Free Syrian Army holds Sunni villages whose residents are calling for the fall of President Bashar al-Assad. On the other side, less than a mile away, villagers from Assad’s Alawite minority remain fiercely loyal to the government and gladly host army checkpoints that fire shells and mortars into neighboring Sunni villages.

Both sides in the conflict think they are working to make the country safe for their families and for the future. Both sides blame each other for the death, destruction and fighting. Both sides express longing for a return to peace. And, as Syria Behind the Lines reveals in stark, gripping detail, both sides believe that peace can only be achieved if they are the victors.

Syria Behind the Lines airs Tuesday, April 9 on PBS. (Check your local listings.)