That is, Syria has become at least the 14th country in the Islamic world that U.S. forces have invaded or occupied or bombed, and in which American soldiers have killed or been killed. And that's just since 1980.
Let's tick them off: Iran (1980, 1987-1988), Libya (1981, 1986, 1989, 2011), Lebanon (1983), Kuwait (1991), Iraq (1991-2011, 2014-), Somalia (1992-1993, 2007-), Bosnia (1995), Saudi Arabia (1991, 1996), Afghanistan (1998, 2001-), Sudan (1998), Kosovo (1999), Yemen (2000, 2002-), Pakistan (2004-) and now Syria. Whew.
With our 14th front barely opened, the Pentagon foresees a campaign likely to last for years. Yet even at this early date, this much already seems clear: Even if we win, we lose. Defeating the Islamic State would only commit the United States more deeply to a decades-old enterprise that has proved costly and counterproductive.