Throughout the Chimeran War, America was initially neutral in the conflict until the military liberation of the United Kingdom. Ultimately, America was invaded by the Chimera in August 14th, 1951. From August to November, the Upper Midwest fell under gray territory, creating a war front in the north. The invasion resulted in millions of displaced refugees being forced to resettle in Protection Camps within and near the Liberty Defense Perimeter or living in makeshift shanty towns, and food shortages became rampant due to the Chimera's weather-changing technology affecting the nation's farmlands. President Grace, fearing that America will not survive from the technologically superior Chimera, decided on negotiating with the Chimera to spare America at the expense of the world.
The terms of the intended truce were basically that America would not impede the Chimera in their conquest of the world, in exchange for the Chimera leaving America in peace. However, Grace and his cabinet realized that the Chimeran entity known as Daedalus was the only Chimeran being that is communicable in the negotiations and that capturing him remains the top priority in the negotiations. Presidential Chief of Staff William Dentweiler was tasked in overseeing the capture of Daedalus.
Learning that Daedalus possessed superior mental powers and still retaining his human feelings for his wife, Hannah Shepherd, Dentweiler procured Hannah to Sheridan, Wyoming and had government agents tortured her in sending a mental signal to Daedalus and lure him to rescue his wife. After Chimeran forces dispatched by Daedalus rescued Hannah, American forces followed them to Daedalus' location due to a tracking transmitter implanted in Hannah's hair, and were able to capture Daedalus by firing harpoons containing 2000 cc of sedatives into the creature. Daedalus was later brought and confined in a secret facility near Sheridan and implanted with a electrode to prevent him from using his powers. Furthermore, in order to ensure Daedalus' cooperation in the negotiations, Hannah was kept at Sheridan to be used as a hostage.
On December 24th, President Grace traveled to Sheridan, under the guise of his Victory Tour, to negotiate with Daedalus and revealed his offer. Daedalus, however, inwardly laughed at Grace's offer and had no intentions of honoring it. Just after Grace finished giving his offer to Daedalus, the President was abrupt killed by the Sentinel Nathan Hale, who had learned about Grace's insidious treachery from the audio recordings of former Secretary of War Henry Walker. Shortly after Grace's death, Daedalus took advantage of the chaos to escape from his confinement to the safety of a nearby Chimeran warship that was present outside of Sheridan, as part of the negotiations. Before departing, Daedalus ordered the ship to destroy Sheridan and its surroundings in retaliation for his captivity.
The knowledge of Project Omega and the death of Noah Grace was secretly covered up and supposed negotiations between the Chimera and the United States was entirely dashed. Grace's death was announced by his successor Vice President Harvey McCullen on December 25th, blaming his predecessor's cause of death as a "sudden illness."