The U.S., which has built a coalition with the aim of eradicating the Islamic State of Iraq and al-Sham (ISIS), has so far been unsuccessful in reaching its aim. The coalition has been pounding ISIS targets in Iraq and Syria, especially in Kobani, for several weeks. Besides the airstrikes, the armed U.S.-backed Kurdish factions under the leadership of PKK's official Syrian branch Democratic Union Party (PYD) and its armed wing People's Protection Units (YPG) are trying to defend the town. However, weeks of U.S.-led air strikes on the insurgents' positions around Kobani and the deaths of hundreds of their fighters have failed to break the siege on the town. Moreover, the U.S. has spent more than a billion dollars so far during the operations and the cost is likely raise since ISIS still makes advances in some Syrian cities and battles against the Iraqi security forces.Besides the cost and the ineffectiveness, some U.S. officials voiced their concerns on that the operations may help Syrian President Bashar al-Assad to remain in power and be strengthened despite the U.S.-backed 'moderate' opposition groups continue fighting. However, since the anti-ISIS operations started which targets not only ISIS but also al-Qaida-linked Nusra Front, Assad regime has made advances in rebel-held areas and carried out airstrikes after a weeks-long silence.White House National Security Adviser Susan Rice said the solution in Syria will "ultimately have to result in Assad's departure." She added, "You have an illegitimate and exceedingly violent leadership that has created conditions not only that have been so harmful to the population, but have made it a very attractive magnet for terrorists," while speaking at the Harman Center for the Arts based in Washington. After Rice, U.S. Pentagon chief Chuck Hagel stressed the need for honesty in internal government discussions on Thursday as he declined comment on a two-page internal memo he wrote on Syria policy, described as critical by people familiar with its contents. The memo from Hagel to Rice was first reported by the New York Times, which said he warned U.S. President Barack Obama's Syria policy was in jeopardy due to its failure to clarify its intentions toward Assad. Hagel warned on Thursday that Syrian President Bashar al-Assad may "benefit" from U.S.-led airstrikes targeting ISIS. "As we and the coalition go after ISIS to help the Iraqis secure their government, but also the Middle East, yes, Assad derives some benefit of that, of course," Hagel said. Asked about the memo, Hagel told a Pentagon news conference: "We owe the president and we owe the National Security Council our best thinking on this." "And it has to be honest and it has to be direct," Hagel said, without citing areas of disagreement. "The fighting can go on for years and years to what end? ... It's in our interest not to have an unstable Middle East," Hagel said, stressing the need to manage current threats while focusing on "some longer term strategies and objectives."Obama faces criticism at home and abroad for looking at the crisis in Syria almost exclusively through the threat of ISIS.The war in Syria, which started in March 2011 with pro-democracy protests but rapidly grew into a horrific civil war, has caused the death of more than 200,000 people and at least 60,000 are missing. The war also displaced nearly 10 million people. The Assad regime has been accused of committing war crimes against civilians by insurgent groups.