Nerguizan adds that arming anti-Assad fighters carries risks, as well.

"We do not know whether these are players that can reliably be armed so that these weapons do not become a proliferation risk," Nerguizian explained. "You have enormous risks of these weapons falling into the hands of players that are anything but favorable to U.S. interests in the region."

But with a mounting death toll in Syria, calls for a more-assertive international response are growing.

"How many more have to die? 10,000 more, 20,000 more? How many more," asked McCain.

For now, U.S. officials will only say that military options are being developed.

"The Defense Department - as we always do - is reviewing and is continuing to review plans for a wide variety of possible scenarios should the president determine that further steps are necessary," Panetta explained.

And analyst Aram Nerguizian approves of the current U.S. approach.

"There needs to be some degree of patience," Nerguizian added.

Meanwhile, the international community's patience is being tested as the slaughter in Syria continues.