Our embassy in Ankara is in danger and has been for a long time. The detention of a gunman shooting outside of the embassy is just one indication of the danger there. Ankara is unstable and dangerous for U.S. citizens and those in diplomatic and government roles should be very cautious to protect themselves from impending danger.
It would be foolish to believe that there are no threats to embassies in any foreign country. ISIS and other terrorist organizations have made no secrete of the fact that they intend to attack the US both at home and abroad. The gunman in Ankara is just a drop in the bucket compared to the people who would attack the US if given the opportunity.
The world is in a state of ever-increasing turmoil, with the U.S. generally being right in the center of the conflict. The fact that this has happened once again only reinforces the fact that our country is not well-liked by many others. The Embassy is certainly in danger, and is likely to remain as such.
By launching attacks on people at embassies, terrorists are able to strike against many countries at one time. The diplomats and other embassy personnel represent many countries and an attack on an embassy is a strike against the citizens of those countries, even thought they may be located far away.