WASHINGTON (AP) -- Two senior senators pressed Gen. Martin Dempsey, the chairman of the Joint Chiefs of Staff, for his assessment about the use of U.S. military force in Syria as Dempsey's reluctance to give Congress his personal opinion threatens his nomination.
Sen. Carl Levin, D-Mich., chairman of the Armed Services Committee, and Sen. John McCain, R-Ariz., sent a letter to Dempsey on Friday with 11 extensive questions about Syria as well as the ongoing war in Afghanistan.
The letter comes a day after McCain and Dempsey tangled at a congressional hearing. The GOP lawmaker said he would block Dempsey's nomination to a second term until he gets an adequate response from the senior military official.
McCain and Levin have been pushing for a more aggressive response by the Obama administration to the deadly civil war that has killed an estimated 93,000 and displaced millions of Syrians, creating a humanitarian crisis in neighboring countries such as Jordan.
Among the questions was a request for Dempsey's assessment of the "costs, benefits and risks associated with training and arming vetted elements of the Syrian opposition? In your view, could such action alone be sufficient to adequately build the military capability of the moderate opposition in Syria and create the necessary conditions for the administration's stated policy objective -- Bashar Assad's departure and a negotiated solution to the conflict in Syria -- to succeed?"
The senators also asked Dempsey whether the U.S. military has the ability to significantly reduce Syria's air power, ballistic missiles and heavy artillery, and whether taking that step would shift the balance of power in the civil war.
Col. Edward Thomas, a spokesman for Dempsey, said the military leader would respond to the request.
"The chairman respects the confirmation process and, if confirmed for another two-year term, will be honored to serve at the pleasure of the president and with the consent of Congress," Thomas said.
At the hearing Thursday, McCain asked Dempsey to provide his personal opinion on which approach in Syria carries greater risk for U.S. national security interests: continued limited action on the part of Washington, or more significant steps such as establishment of a no-fly zone and arming rebel forces with the weapons they need to stem the advance of Assad's forces.
Dempsey said he has provided President Barack Obama with options for the use of U.S. military force in Syria, but he declined to detail those choices.
"It would be inappropriate for me to try to influence the decision with me rendering an opinion in public about what kind of force we should use," Dempsey said.
Dempsey added that the question of whether to support the opposition forces in Syria "with direct kinetic strikes ... is a decision for our elected officials, not for the senior military leader of the nation."
The use of kinetic strikes, a military term that typically refers to missiles and bombs, "is under deliberation inside of our agencies of government," he said.
Dempsey's response, McCain said, contradicted his commitment to provide the committee with his personal views, even if those opinions differ from the administration in power.
McCain told reporters after leaving the hearing room that he planned to put a hold on the nomination, essentially blocking any further action until he gets acceptable answers from Dempsey.
The letter also seeks Dempsey's assessment of the Afghan National Security Forces and the risks associated with drawing down U.S. forces in Afghanistan.
Associated Press writers Richard Lardner and Robert Burns contributed to this report.
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