The Battle of Washington, D.C. was a clash between Captain America and the brainwashed Winter Soldier during the HYDRA Uprising. After Arnim Zola revealed that HYDRA was active for the past seven decades, Captain America and Black Widow recruited Sam Wilson to fight alongside them as the Falcon.
Arnim Zola revealed that HYDRA, despite the defeat of the Red Skull, had been growing inside S.H.I.E.L.D.for the past 70 years to Steve Rogers and Natasha Romanoff, only to result in HYDRA ordering an airstrike on their location, killing Zola.
Rogers and Romanoff laid low in Sam Wilson's apartment, a friend whom Rogers met previously during a morning run. Wilson revealed his past as a parajumper and equipment that he had used during his career in the military.
Rogers and Romanoff figured that Jasper Sitwell knew information regarding Zola's algorithm. The trio went to Fort Meade to retrieve the EXO-7 Falcon wings.
Wilson brought Sitwell to the top of a building in downtown Washington, D.C. and the team forced him to reveal the true intentions of Project Insight.