It's a "parody" (for lack of a better word) of the CoD: Modern Warfare 2 level: "Second Sun". The building in the background was in the Washington DC levels, and "Second Sun" involved you waking up from your crashed helicopter and (seemingly) fighting to the last man.(or girl in this case.)
Spin226 said: Romeo Hotel, this is Charlie Niner requesting immediate assistance!
Uh... negative Charlie Niner. All available ground-teams are heading to the target building west of your position. Proceed to the target building and provide support. Out.
Kensleyli said: Charlie Niner, this is Romeo Hotel. Evacuation Order April have been issued. You and your team have to get to the last helicopter at the Washington Monument. You have less than 30-seconds. Good luck. Out
Cirno: Negative! Repeat; Negative! We are pinned down by heavy enemy ground forces and helios- what the hell *EMP hits DC*