A powerful explosion went off in Istanbul near the city's most prominent tourist attractions on Jan. 12, killing at least 10 people and injuring six foreign tourists. The blast, which took place in front of the ancient Egyptian Obelisk of Theodosius and near the Blue Mosque in the Sultanahmet district, reportedly involved a suicide bomber. Though the Turkish government is currently in conflict with numerous terrorist and non-state militant groups, the location, target and method of attack point to the Islamic State as the primary suspect behind the operation. In comments made after an hourlong meeting of the country's National Security Council, Turkish President Recep Tayyip Erdogan said the suicide bomber was of Syrian origin.
By cracking down on the Islamic State and actively supporting rebel operations against the extremist group in Syria, Turkey has knowingly made itself a target of the many groups loyal to the Islamic State. Furious at the disruption of their vital supply lines through Turkey because of the crackdown, which has steadily intensified since July 2015, Islamic State leaders have repeatedly vowed to launch severe retaliatory attacks. The first serious attack occurred last year on July 20, when the group staged a suicide bombing attack in the Turkish town of Suruc, near the Syrian border. Turkish raids and arrests stopped several other planned attacks, but not all of them; on Oct. 10, the group struck again in Ankara.
The latest attack, which hit in the heart of Istanbul's oldest quarter, could galvanize an even stronger Turkish response against the Islamic State. Indeed, Ankara has already been pushing its allies to support it in an operation in Syria's northern Aleppo province that aims to create a buffer zone in the Azaz-Jarablus zone. A successful operation would serve Turkish interests by hurting the Islamic State, strengthening the rebel position in northern Syria, preventing the Kurdish People's Protection Units (YPG) from expanding farther westward and — because Turkey does not want to go it alone — drawing the United States deeper into the conflict.
However, Russia's intervention in Syria has greatly complicated Turkey’s plans for the operation, and in the wake of Turkey shooting down a Russian Su-24 warplane, Moscow continues to frustrate Turkish ambitions in the country. The Russians, for instance, have reinforced their air defense assets in Syria, and in a Dec. 17 interview, Russian President Vladimir Putin dared Turkey to fly over Syrian airspace with the implication that the aircraft would be shot down if it did. Faced with the prospect of a potential war with Russia if it proceeded with an armed incursion into Syria, Ankara has been forced to revise its plans for northern Aleppo.
In spite of the risk that Russia poses, Turkey could increase its involvement in Syria. This latest Islamic State attack on a Turkish city comes at a time when the Kurdish-dominated Syrian Democratic Forces have crossed the Euphrates River in their push westward and Russian- and Iranian-backed loyalist offensives have ratcheted up the pressure on Turkey's Syrian rebel proxies. The Turks may choose to carry out intensified strikes with long-range missiles from the safety of their own borders, but a greater Turkish incursion into Syria cannot be ruled out.