The United States has agreed to send two Patriot missile batteries to defend Turkey's border against Syria missiles, and that also means 400 more American troops will be on the ground and closer than ever to the ongoing fight in Syria. Germany and the Netherlands will also contribute missile teams to the effort following NATO's approval of the plan last week. Secretary of Defense Leon Panetta signed the order personally on Friday morning after arriving in Turkey on an unannounced visit to the US Air Force Base in Incirlik.

It will take several weeks before the soldiers can actually be deployed overseas, but the mere announcement of the show of force is meant to deter Syria from even considering an attack on southern Turkey, where hundreds of thousands of Syrian citizens have fled to refugee camps, and where many of the supplies being fed to the rebel armies originate. 

The presence of U.S. troops will be more than just symbolism, however. The deployment marks a major increase in the U.S. role in the conflict, placing Americans within striking distance of Syrian weapons—and within range of striking back. Should the Patriots actually be called upon in defense of Turkey, American forces would suddenly find themselves a direct participant in the civil war, making it easier for them escalate even further and possibly to become an attractive target should Bashar al-Assad decided to make one final desperate act against his enemies.