(CBS News) DAMASCUS, Syria - Civil war has not -- so far -- disrupted the ritual of Sunday mass at Al Zeytouna Greek Catholic Church in Damascus. But Father Fadi al-Hamseh, like every member of this congregation, is deeply worried.
Several hundred thousand Christians in Syria fear an American attack could lead to their widespread persecution by weakening the Assad government and strengthening Islamic rebels, many of them linked to al Qaeda.
The members of the Al Zeytouna Greek Catholic Church have seen the videos posted online and heard the news that Islamist rebels pushed past the Syrian army and, just forty miles north of the capital.
The Syrian government now claims its troops are back in control. Al Zeytouna worshippers pray that's true, but the threat feels very close.
Just two weeks ago, four mortars were fired into a Christian neighborhood in Damascus, where everyone knows everyone.
A local man, Agor, was killed.
"He was 42 years old," said a neighbor, named Fadi. "He was a family man, had three children. He was my friend, really.
Christians have flourished under the protection of President Bashar Assad, but there's widespread fear that era has ended as Muslim extremists gain power within the armed opposition.
"They are trying to force us to go out or die, if we try stay we will die," Fadi said.
No one is saying ethnic cleansing yet, but they're thinking it. Christians are not the only ones fearing for their life. Minority groups in Syria do not all agree with President Assad, but they say that he at least keeps them safe. If he goes, they fear a blood bath.
Watch: Barry Peterson reports how Christians are under attack in Syria.