In October 2020, the United States arrested former Mexican Defense Secretary General Salvador Cienfuegos Zepeda on drug conspiracy charges, accusing him of accepting bribes to aid a Mexican cartel in evading law enforcement and transporting drugs into the United States. Cienfuegos's arrest sparked diplomatic protests from Mexico, which negotiated to gain Cienfuegos's release before exonerating him and publicizing the U.S. investigation file in what the United States called a breach of the countries’ mutual legal assistance treaty. The incident also prompted Mexico to pass a new law curtailing cooperation with foreign agents and potentially imperiling the long-standing U.S.-Mexico alliance in the fight against cross-border drug trafficking.

As the COVID-19 pandemic continues to rage across the world, the United States and its allies are pushing for answers about the virus's origins while China rebuffs inquiry into its early handling of the outbreak. Meanwhile, a growing U.S. stockpile of vaccines has opened new avenues for “vaccine diplomacy,” and the Biden administration has thrown its weight behind an effort to suspend cross-border intellectual property (IP) rules for vaccine manufacturing. In the near term, however, experts expect vaccination rates and access will continue to vary widely between countries depending on their wealth.

On February 1, 2021, the military in Burma overthrew the democratically elected government, declared a one-year state of emergency, and installed Senior General Min Aung Hlaing as the head of government. Since the coup, the military has cracked down on protestors, killing over 800 people and detaining many more. Numerous countries and international organizations, including the United States and the United Nations, have condemned the coup and ensuing violence and called for the restoration of a democratic government. The United States and other countries have also imposed rigorous sanctions on the Burmese military, its officials and affiliated corporations, and social media companies have imposed content restrictions to prevent the spread of pro-military propaganda.

In June 2019, protests erupted in Hong Kong after its government proposed an extradition agreement with mainland China. Alarmed by the protests, the Central Committee of the Chinese Communist Party announced that it would consider new national security measures for Hong Kong. On June 30, 2020, China's National People's Congress Standing Committee (NPCSC) passed the “Law of the People's Republic of China on Safeguarding National Security in the Hong Kong Special Administrative Region.” While the law was under consideration, the United States responded by declaring that Hong Kong was no longer significantly autonomous from mainland China and beginning the process of ending Hong Kong's special status under U.S. law. The United States and its allies continue to criticize Hong Kong's deteriorating autonomy from China, pointing to the postponement of elections in Hong Kong as further evidence.

On September 2, 2020, the Trump administration announced that the United States had added the International Criminal Court (ICC) prosecutor, Fatou Bensouda, and the head of the Office of the Prosecutor's Jurisdiction, Complementarity, and Cooperation Division, Phakiso Mochochoko, to the Treasury Department's Office of Foreign Assets Control List of Specially Designated Nationals and Blocked Persons. The action followed Executive Order 13,928, signed in June, which authorized economic sanctions and visa restrictions on ICC employees who are investigating whether U.S. forces committed war crimes in Afghanistan. Governments and human rights groups decried the sanctions as an attack on international justice.

In Nestlé USA, Inc. v. Doe, et al., former child slaves who were trafficked into Côte d'Ivoire to work on cocoa farms filed suit under the Alien Tort Statute (ATS) against U.S.-based companies that purchase cocoa from and provide other support to the farms, alleging that the companies aided and abetted child slavery. By an 8–1 vote, the Supreme Court held that the case involved an impermissible extraterritorial application of the ATS under the Court's precedent in Kiobel. The Court declined to resolve whether domestic corporations may be held liable under the ATS, although five justices across several opinions expressed the view that such corporations are not immune from ATS suits. The question of whether the Court should ever create new causes of action under the ATS prompted significant debate, with three justices suggesting that they would overrule Sosa v. Álvarez-Machain and a fourth indicating that there are strong arguments to reject judicial creation of any new ATS causes of action.

On February 25, 2021, the United States conducted a strike targeting Iranian-backed militia group facilities in Syria. The strike, which came in response to a February 15, 2021 attack on U.S. interests in Iraq, marked the Biden administration's first known exercise of executive war powers. As domestic authority for the strike, President Joseph Biden, Jr. cited his authority under Article II of the U.S. Constitution and did not rely on the 2001 or 2002 Authorizations for the Use of Military Force (AUMFs). For international legal authority, Biden relied on individual self-defense under Article 51 of the UN Charter, stating that Syria was “unwilling or unable” to prevent further attacks on the United States by these non-state actors within its territory. The strikes garnered mixed reactions from Congress, where efforts are underway to repeal or reform extant AUMFs as well as the War Powers Resolution (WPR). The Biden administration is also undertaking a review of current U.S. military policy on the use of force, and during this process, it has prohibited drone strikes outside of conventional battlefields, absent presidential approval.

After taking office, the Biden administration quickly moved to reverse or revoke a number of the Trump administration's immigration-related policies. On inauguration day, President Joseph Biden announced several significant changes, including termination of the national emergency at the southern border, halting border wall construction, and removal of discriminatory travel restrictions imposed primarily on Muslim-majority countries. In the following weeks, Biden continued to reverse Trump administration policies, including by overhauling the asylum-seeker regime, creating task forces to undo the harms caused by Trump-era border practices, and reimposing some COVID-related travel restrictions, while revoking others. The Biden administration's proposed immigration legislation could introduce even broader reforms going forward.

The United States withdrew from the Joint Comprehensive Plan of Action (JCPOA) on May 8, 2018, and subsequently reimposed a range of unilateral sanctions on Iran. Throughout mid-2020, the Trump administration sought multilateral support for renewed UN sanctions against Iran, but the Security Council rejected those efforts. In response, the administration moved to initiate snapback sanctions under the terms of the JCPOA and UN Security Council Resolution 2231. However, JCPOA participants and the Security Council largely rebuffed the administration's contention that it could activate the snapback mechanism, instead taking the position that U.S. withdrawal from the JCPOA means that it is no longer a “participant state” as required to invoke snapback sanctions.

Nearly twenty years after the U.S. military began operations against the Taliban in Afghanistan, President Joseph R. Biden reported on August 31, 2021, that the last U.S. combat troops had departed the country. Biden announced on April 14, 2021, that the United States would withdraw combat troops from Afghanistan before the twenty-year anniversary of September 11, 2001, and NATO member states decided to depart the country simultaneously. The withdrawal followed an early 2020 deal between the Taliban and the Trump administration, which conditioned the pullout on Taliban agreement not to harbor terrorists that target the United States and its allies. Over the course of a week and a half in mid-August, the Taliban captured most of Afghanistan's provincial capitals, entering Kabul on August 15. The Afghan government collapsed, and President Ashraf Ghani fled the country. Through the end of August, the United States and other countries conducted a major airlift operation to evacuate their nationals and Afghans considered at risk of Taliban reprisals, though many were left behind amid risks of renewed civil war and humanitarian crisis.

Longstanding tensions between Congress and the executive over U.S. support to the Saudi-led coalition in Yemen have spurred conflict between the branches over arms sales. In May 2019, U.S. Secretary of State Michael Pompeo declared an emergency under the Arms Export Control Act (AECA) to bypass congressional “freezes” on arms sales and complete $8.1 billion in sales to members of the Saudi-led coalition. In response, Congress requested that the State Department inspector general (IG) investigate the matter. In a report released in August 2020, the IG determined that the emergency declaration comported with the AECA's procedural requirements but that the State Department's risk assessments and civilian casualty mitigation measures did not fully address legal concerns about the sales. The Trump administration has continued to move forward with arms sales, including by unilaterally reinterpreting a nonbinding multilateral export control regime to eliminate prohibitions on the export of certain unmanned aerial systems (UAS). A bipartisan group of legislators has introduced a bill to prevent such sales to all countries except select U.S. allies. In September, a UN report criticized U.S. and other countries’ arms sales to the Saudi-led coalition and recommended referral of the situation in Yemen to the International Criminal Court (ICC).

The COVID-19 pandemic generated wide interest in global health law (GHL). The ease of its spread, and its eruption at a time of massive global travel in a city that is a major transport hub, turned it into an unprecedented event in the post-World War II era.

Rescuing Human Rights: A Radically Moderate Approach (Rescuing) was published shortly before the outbreak in 2020 of the novel coronavirus and its myriad human rights and class issues regarding equality, discrimination, health, and labor rights of people of color. This was also prior to the concurrent public murder of George Floyd as an unarmed Black man by the Minneapolis police in late May 2020, and the resulting continuing Black Lives Matter massive national and international movement against the deaths of Floyd and others and the history of systemic American racism, including police shooting deaths, discrimination, and brutality against African Americans, particularly unarmed Black men. Such comprehensive street protests have not been seen in America since 1968. They represent, inter alia, the cover of disguises of national racism being publicly stripped away, and the national confrontation with irrefutable evidence of a wide spectrum of systemic rights violations and the deficits of American law and government to ensure African Americans’ basic rights. Further, Rescuing was published before it became fully apparent that the federal government's responses to Black Lives Matter, particularly the executive branch, would fan the racial conflicts of national mourning and demands for new justice narratives, rather than healing and unifying for American citizens as a whole, even as these protests were the most diverse in recent memory.