The nation's top military officials are likely to face sharp questions on Thursday from Republicans angry the Obama administration is not taking more aggressive steps to end the 5-year-old-civil war in Syria.

Defense Secretary Ash Carter and Gen. Joseph Dunford, the chairman of the Joint Chiefs of Staff, are scheduled to appear before the GOP-led Senate Armed Services Committee after the latest attempt to secure a cease-fire in Syria all but collapsed. Republicans are skeptical, even hostile, to the idea that Russia is a willing partner for peace and would work with the United States to combat Islamic State militants and al-Qaida.

Sen. Lindsey Graham, R-S.C., a defense hawk and one of President Barack Obama's most vocal critics, said he anticipates the hearing will be contentious because of the mounting frustration among lawmakers over the lack of a coherent strategy for ending the conflict.

"I expect this to be confrontational," Graham said. "At the end of the day, I think Congress needs to challenge what's going on in Syria."

The failure to establish a no-fly zone in the country's north to protect Syrians from the bombing has been a mistake, according to Graham, and he also criticized the reliance on the Kurdish fighters the U.S. has been supporting in the fight against the Islamic State. Although the battle-hardened Kurds have proven to be effective, their success has alarmed Turkey, which is grappling with a Kurdish insurgency in its southeast.

Although Turkey has repeatedly called for a no-fly zone, the Obama administration has resisted, unwilling to wade too deeply into an intractable conflict.

Sen. John McCain, R-Ariz., the chairman of the Armed Services Committee, had expressed doubt from the start that the cease-fire in Syria would hold. McCain said Obama and Secretary of State John Kerry have "deluded themselves" into believing they could negotiate deals that involve Syrian President Bashar Assad and his chief backers, Russia and Iran.

Tensions between Russia and the United States have only heightened in recent days after authorities in Washington determined with a very high degree of confidence that an attack on a humanitarian aid convoy in Syria earlier this week was carried out by a Russian piloted aircraft. The strike on the Syrian Arab Red Crescent convoy killed 20 civilians.

Washington had said initially that Russia was to blame, but that the strike delivered by a Russian-made Su-24 could have been carried out by Russia or Syria. Both militaries use Su-24 fighter jets. But officials said Wednesday the U.S. has gathered enough intelligence to conclude that Russia, not Syria, launched the airstrike.

Kerry called for all warplanes to halt flights over aid routes and at a U.N. Security Council session he raised "profound doubt" about Russia and Syria's willingness to abide by the cease-fire.

The Sept. 9 truce envisioned a U.S.-Russian military partnership against the Islamic State and al-Qaida if violence was reduced and aid delivered over the course of seven continuous days.

The Pentagon, however, voiced reservations about coordinating air strikes and sharing intelligence with Russia.


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