In what has become an annual tradition, volunteers join Paul Monti, whose son died while serving in Afghanistan, to plant flags at each gravestone at the Massachusetts National Cemetery.
The revolt against the Syrian regime is now more than a year old and has claimed an estimated 10,000 lives.
This week, international outrage has flared up after reports of more than 100 civilians killed in the village of Houla.
So how has President Bashar Assad been able to hold onto power when other Middle Eastern leaders have fallen?
One reason could be that Assad, and his wife, Asma, still enjoy support across the country from people of all walks of life. They also have support in all of Syria’s religious communities.
But ultimately, economic issues could undermine Assad.
The international community is putting increased pressure on Syria, and the economy is now beginning to fail, which could turn Assad’s supporters into dissenters and damage his ability to maintain power.
Peter O’Dowd follows the route of Abraham Lincoln's funeral train 150 years ago, to look at modern-day race relations and Lincoln's legacy.