WASHINGTON - The United States believes Turkey should become more active in the air war against Islamic State, secure its border and go after the militant group's facilitators who "intrude" into Turkey, US Defense Secretary Ash Carter said on Tuesday."We need it to do more within its own territory, so it controls its border, which it has not done effectively since ISIL first arose," Carter told a hearing in Congress, using an acronym for the Islamic State."We would like them to operate more both in the air and on the ground. Most of the air operations are not directed at ISIL. They are directed at the PKK," he added, referring to the Kurdistan Workers' Party (PKK) militant group.