http://www.bbc.co.uk/news/world-us-canada-23849386
" Forces which could be used against Syria:
Four US destroyers - USS Gravely, USS Ramage, USS Barry and USS Mahan - are in the eastern Mediterranean, equipped with cruise missiles
Cruise missiles could also be launched from submarines, including a British Trafalgar class boat. HMS Tireless was reportedly sighted in Gibraltar at the weekend
Airbases at Incirlik and Izmir in Turkey, and in Jordan, could be used to carry out strikes