New Travel Warnings Likely Due to Possible Action in Syria

The U.S. State Department will most certainly be updating its travel warnings based on imminent action against Syria.

In past conflicts such warnings came after the fact.  U.S. citizens and travelers are well advised to be prepared to alter plans based on what might happen in the next few days. 

From the State Department website:
Travel Warnings are issued when long-term, protracted conditions that make a country dangerous or unstable lead the State Department to recommend that Americans avoid or consider the risk of travel to that country. A Travel Warning is also issued when the U.S. Government's ability to assist American citizens is constrained due to the closure of an embassy or consulate or because of a drawdown of its staff. The countries listed below meet those criteria:
Algeria 08/23/2013
Afghanistan 08/23/2013
Egypt 08/15/2013
Haiti 08/13/2013
El Salvador 08/09/2013
Pakistan 08/09/2013
Yemen 08/06/2013
Saudi Arabia 07/25/2013
Mali 07/18/2013
Niger 07/15/2013
Mexico 07/12/2013
Philippines 07/05/2013
Kenya 07/05/2013
Somalia 06/21/2013
Israel, the West Bank and Gaza 06/19/2013
Honduras 06/17/2013
Chad 06/11/2013
Libya 06/07/2013
Nigeria 06/03/2013
Iran 05/24/2013
Mauritania 05/21/2013
Cote d'Ivoire 05/16/2013
Eritrea 05/10/2013
Central African Republic 05/10/2013
Congo, Democratic Republic of the 04/24/2013
Burundi 04/22/2013
Sudan 04/16/2013
Colombia 04/11/2013
Lebanon 04/01/2013
Republic of South Sudan 03/29/2013
Korea, Democratic People's Republic of 03/14/2013
Guinea 03/14/2013
Tunisia 03/13/2013
Syria 03/01/2013
Iraq 02/25/2013