Just hours after new details on the game came to light, Activision has launched the first of likely many teaser trailers for Call of Duty: Modern Warfare 3 via Facebook. Subtitled "America Under Siege," the all-too-brief clip drives home the fact that a focus of the modern combat occurring in this installment will be the USA's own front lawn.

Enough explaining -- you can watch the 30 second video (reminiscent of the one used to debut Modern Warfare 2 in 2009) after the break, after which we're sure you'll have all sorts of plot theories to share in comments. Make us proud!

Update: We've added three more clips from Activision just after the break, teasing France, England, and Germany.

[Thanks to everyone who sent this in!]