Turkey appeared to take a big political step toward joining the American-led campaign against the militants of the Islamic State when its Parliament voted Thursday to authorize expanded military operations in Iraq and Syria and to allow foreign forces to launch operations from its territory. But it was far from clear whether the political step would soon translate into military action. In many ways Turkey’s stance is a crucial question mark hanging over the campaign against the Islamic State. Alone among the potential coalition members, it has a large, capable army already on station along the borders of Syria and Iraq, with bases and logistical support close at hand and long experience at working with other NATO members, including the United States. But it has been deeply cautious about intervening against the Islamic State, also known as ISIS, and the militants have so far been careful not to draw […]