The top U.S. military officer has warned that intervening in Syria's civil war would cost billions of dollars, might escalate quickly and could turn into a highly risky endeavor for the United States.
General Martin Dempsey, chairman of the Joint Chiefs of Staff, provided a list of options for Congress to halt Syria's bloody conflict. It is the first time the Pentagon has explicitly described what it sees as the potential "unintended consequences" from any overt U.S. military action.
Dempsey's letter to Sens. John McCain and Carl Levin, released late Monday, detailed options ranging from training opposition forces to conducting airstrikes and enforcing a no-fly zone over Syria.
Long-range strikes on Syrian military targets, he noted, would require "hundreds of aircraft, ships, submarines and other enablers," and cost "in the billions."
Thousands of U.S. troops would be required if Washington wanted to establish buffer zones to protect certain geographic areas or control the proliferation of chemical weapons, the letter asserted.
It followed a testy exchange at a congressional hearing last week between Dempsey and McCain, a leading advocate of intervention, when the general testified about why the U.S. is not doing more to help opposition rebels fighting to oust Syrian President Bashar al-Assad.
'Worst case scenario'
Dempsey's letter outlined a "worst-case scenario" and is not the final word on the issue, according to Steven Heydemann, an analyst at the Washington-based United States Institute of Peace.
"He seemed to feel the U.S. would be acting alone if it were to pursue any of these options. He seemed to argue that any one of the options he discussed would require massive commitment of U.S. forces when it may be the case that the goals he outlined could be achieved through a variety of different force levels," Heydemann said.
McCain has led calls in Congress to arm the rebels and establish a no-fly zone to protect opposition forces from Assad's air power.
Heydemann said the Obama administration's goals and those of intervention supporters like McCain both involve forcing the Syrian government to the negotiating table.
"It's understood that our strategy has a military dimension, that the best way to arrive at negotiations is to create conditions on the ground that will compel the Assad regime to recognize that negotiations represent its best option for securing some sort of future for itself in a post-conflict Syria," said Heydemann.
But U.S. Congressman Trey Radel, who is sponsoring an amendment on Syria to the defense appropriations bill being debated on the House floor, is among those strongly opposed to the direct insertion of U.S. ground troops into the conflict.
"I simply want to re-assert that Congress decides when or if we are ever going to put boots on the ground, in this case with Syria. And I do not support putting boots on the ground, our young men and women in harm's way in Syria. It is a civil war," Radel said.
These debates come as the White House, which is moving ahead with a limited plan to supply the rebels with small arms and other weapons, has begun to acknowledge that Assad may remain in power for the foreseeable future.