Early Thursday morning, the Internet in Syria went dark. Technology analysts suspect the Syrian government was behind the action, perhaps as part of an effort to blunt advances by rebel forces. Governments in recent years have become more mindful of the potentially subversive power of the Internet and also more knowledgeable about how to shut it down. The outage in Syria underscores the importance of current disputes over who should control the global Internet. That issue is the focus of a major international conference next week in Dubai.