WASHINGTON - Washington's attention will be split this week between the conflict in Syria and the legislative push to overhaul America's immigration system. Syria's protracted civil war is expected to be a prime topic of discussion at this week's G-8 summit in Northern Ireland.

President Barack Obama attends the G-8 forum days after the United States announced it will provide military aid to Syrian rebels.  Deputy National Security Adviser Ben Rhodes said, "We have steadily increased the size and scope of our assistance to the political opposition and the SMC (Supreme Military Council). And we have decided to take an additional step forward and provide dramatically-increased assistance to the SMC going forward."

The decision follows setbacks for the rebels at the hands of forces loyal to Syrian President Bashar al-Assad, and U.S. assessments about chemical weapons.

"We assess with high confidence that Sarin (nerve agent) has been used, and frankly the (Assad) regime retains custody of those weapons," said Rhodes.

U.S. public opinion remains firmly opposed to direct military intervention in Syria, and even the most outspoken congressional advocates of expanded U.S. involvement say there should be no American troop deployments to Syria.

Meanwhile, the U.S. Senate is moving forward on immigration reform.

The chamber voted to begin debate on a bill that would provide a path to citizenship for most of the 11-million undocumented immigrants in the country, and streamline the process for legal immigration.

Such changes are long overdue, according to Democratic Senator Charles Schumer. "Our country, amazingly and counterproductively, turns away hundreds of thousands of people who will create jobs and improve our economy.  And at the same time, we let cross the border millions who take jobs away from American workers," he said.

Senate debate is expected to be long and contentious.  Some Republicans want guarantees of air-tight border security before any undocumented workers are legalized.  Even if the Senate passes a bill, its fate is far from certain in the Republican-controlled House, where Speaker John Boehner has expressed reservations.

"Especially in the area of border security, and internal enforcement of this system, I am concerned that it [the bill] does not go far enough," he said.

President Obama says he wants to sign an immigration reform bill into law in coming months.

The coming week could also see further developments concerning the U.S. government's domestic surveillance program.  And the U.S. Supreme Court is expected to issue landmark rulings on same-sex marriage either this week or next.