Renewed Great Power Competition: Implications for Defense--Issues for Congress [Updated April 7, 2020] [open pdf - 1MB]
From the Summary: "Many observers have concluded that the post-Cold War era of international relations--which began in the early 1990s and is sometimes referred to as the unipolar moment (with the United States as the unipolar power)--began to fade in 2006-2008, and that by 2014, the international environment had shifted to a fundamentally different situation of renewed great power competition with China and Russia and challenges by these two countries and others to elements of the U.S.-led international order that has operated since World War II. The shift to renewed great power competition was acknowledged alongside other considerations in the Obama Administration's June 2015 National Military Strategy, and was placed at the center of the Trump Administration's December 2017 National Security Strategy (NSS) and January 2018 National Defense Strategy (NDS). The December 2017 NSS and January 2018 NDS formally reoriented U.S. national security strategy and U.S. defense strategy toward an explicit primary focus on great power competition with China and Russia. Department of Defense (DOD) officials have subsequently identified countering China's military capabilities as DOD's top priority."
CRS Report for Congress, R43838
Congressional Research Service: https://crsreports.congress.gov/