Stressing the importance of America's Muslim allies in the fight against Islamic extremism, retired Gen. David Petraeus says it's important for the U.S. to avoid portraying the clash as "a clash of civilizations." His comments came in a House Armed Services Committee hearing titled "The State of the World: National Security Threats and Challenges."Asked about President Trump's recent immigration ban, Petraeus said he hopes the security review that was given as a reason for the ban is carried out quickly, saying that the long-term effects of President Trump's order targeting Iraq and six other Muslim-majority countries will depend on how long the ban lasts."We must also remember that Islamic extremists want to portray this fight as a clash of civilizations, with America at war against Islam," Petraeus said Wednesday. "We must not let them do that. Indeed, we must be very sensitive to actions that might give them ammunition in such an effort."Mentioning Iraqis who have worked with the U.S. to fight terrorists and bring stability to their country, Petraeus said that many of them are now in limbo, after undergoing a years-long process of being cleared to travel to the U.S. As an example, he cited Gen. Talib Shaghati Mshari al-Kenani, who heads Iraq's counter-terrorism service, who is now "prevented from coming here to coordinate with Central Command" and visit his family, who were moved to the U.S. for their own safety.The general's response came to a question from Rep. Susan Davis, D-Calif., about how the U.S. travel ban would be interpreted in Iraq, and what its long-term effects might be.Petraeus testified along with a former colleague at the CIA — John McLaughlin, the agency's former deputy director and acting director.When Rep. Davis then asked McLaughlin if he agreed that the travel ban would give ammunition to America's enemies, he answered, "Almost everything we do gives the Islamic extremists ammunition. They can take almost anything, any American policy, and turn it into propaganda. And they will do that with this."Lasting for several hours, the hearing touched on a wide range of topics, from the ambitions of Russia and its President Vladimir Putin to the complexities of dealing with China. But the fight against terrorism, and the unique threat posed by ISIS, was a recurring theme."Our most important ally in this war is the overwhelming majority of Muslims who reject al Qaida, Daesh, and their fanatical, barbaric worldview," Petraeus said. "Indeed, it is millions of Muslims who are fighting and dying in the greatest numbers on the front lines of this war."At that point, Petraeus ran down a list of places where Muslims are fighting extremists, from Iraq, Yemen and Somalia to Libya — all of which are named in President Trump's controversial immigration order.The former general then discussed the dangers to America posed by technologies and strategies that undermine its traditional strengths. And he cited "revisionist powers" such as Russia and China that are seeking to sap America's power and influence.After America's operations in Iraq and Afghanistan showed the might of America's military, Petraeus said, "our adversaries responded with strategies that, for a fraction of the cost, nullified many of our advantages."Petraeus said: