The War on HYDRA was a conflict between the terrorist organization HYDRA and all world governments and security organizations after the revelation of HYDRA's continued existence. At first, HYDRA had the upper hand over S.H.I.E.L.D., because S.H.I.E.L.D. was reduced to only a shadow of its former strength, and the HYDRA leader Daniel Whitehall used that to retrieve the mysterious Obelisk. However, once S.H.I.E.L.D. was redeemed in the eyes of the law, they turned the tables on HYDRA, who lost the battle for the ancient Kree City, and many of its leaders, including Whitehall, in rapid succession. Though Baron von Strucker and Doctor List continued HYDRA's experiments on enhanced people, their efforts were rendered null when their HYDRA cell was destroyed by S.H.I.E.L.D. and the Avengers – on