For those who follow high-tech weapons the following are some of the US military assets that may form part of the armada that may well strike the Syrian regime.
Guided missile destroyers
The US currently has five guided missile destroyers in the eastern Mediterranean Sea - the USS Gravely, the USS Barry, the USS Ramage, the USS Mahan and the USS Stout. Each ship can carry a maximum of 96 Tomahawk cruise missiles if loaded only with those weapons. The actual number they are carrying at any time depends on the mission and what other weapons and systems are needed.Tomahawk missiles are likely to be the weapon of choice if Obama orders a strike because they have a range of about 1,610 kilometres and can be used at a distance without a concerted effort to destroy Syria's integrated air defences.
The US usually has three destroyers in the region. The Mahan was due to rotate back home but was told to remain on station last Friday. The Stout has just arrived in the region to replace one of the other destroyers that was about to depart, the Navy said.
Submarines
The US has 58 nuclear propelled submarines capable of launching Tomahawk cruise missiles, including four designated guided missile submarines capable of carrying up to 154 missiles apiece. The Navy does not discuss the whereabouts of its submarines, but one or more could be tapped for duty if Obama decides to carry out targeted strikes against Syria.Aircraft
US F-22s, F-18s, F-16s, F-15s, B-1, B-2 and B-52 bombers are capable of carrying conventional air-launched cruise missiles and faster rocket powered missiles. Those could be called into play if needed, as they have been in previous conflicts in the Middle East, flying from bases in the US or elsewhere. The air-launched cruise missiles also are stand-off weapons that could be dropped from outside Syrian territory.Aircraft carriers
The USS Harry S. Truman is currently in the northern Arabian Sea and the USS Nimitz is in the Indian Ocean. Aircraft from the two carriers could be called into service if needed to participate in an attack. But their participation appears unlikely. US officials have indicated any strikes against Syria are likely to be limited in scope.Use of aircraft from the carriers would probably require a broader operation involving a US effort to destroy Syria's integrated air defences before sending planes over the country. The Nimitz has been supporting US operations in Afghanistan and is due to be replaced by the Truman, which is crossing the Arabian Sea to relieve the Nimitz so it can return home.
Amphibious assault ship
The USS Kearsarge recently ended a port call in the Gulf and is headed back out to sea. The vessel has a contingent of Marines but is not considered likely to participate in limited operations like the ones Obama is reported to be considering.Additional aircraft at bases in the region
The US has additional aircraft at different bases in the region, in places like Cyprus and Turkey, that could support an operation against Syria if needed. But that is not seen as likely because it would require a much larger effort to remove the threat of Syria's air defences.France
France also has cruise missile capable surface ships, submarines and fast jets.