In face of the outbreak of the COVID-19 pandemic in 2020，The Trump administration have adopted passive anti-epidemic measures，which led to the rapid spread of the virus in the United States. This also had a great negative impact on its political，economic，social，and security environment. The spread of the epidemic，coupled with the social split，has led to the disorder of the internal affairs and the rigidity of the diplomacy of the American government；On one hand，its internal identity politics is turning out to be a “fortress”，and the class contradictions are becoming increasingly prominent. On the other hand，its external offensive posture is escalating and showing strategic shortsightedness. The 2020 U.S. general election is not only closely related to the inherent social contradictions in the U.S.，but also deeply affected by the unexpected factors，such as the coronavirus epidemic. Voters participate enthusiastically，candidates of the two parties are evenly matched，and finally the democratic camp won the election. Throughout the process，the epidemic has become a key variable. In the future，Joe Biden will face the most severe challenges domestically and internationally since the Cold War. Controlling the epidemic，restoring the economy as well as stabilizing its alliance will become his political priority. Although it is difficult for Biden administration to fundamentally reverse the historical abuses of the United States and eliminate the negative effects left over by the Trump administration’s policies，it is still possible to make a breakthrough in some specific policies to delay the arrival of a more serious crisis.