Last week, Secretary of State Mike Pompeo announced diplomatic sanctions against the International Criminal Court. Members of the court investigating war crimes committed during the Afghanistan war will now be denied entry to the United States; Pompeo also threatened economic and financial sanctions unless the ICC drops this investigation.

By using sanctions against the main international judiciary investigating mass-scale atrocities and crimes against humanity, the US government is engaging in a particularly virulent form of power politics. But the assertion of national sovereignty in this arena is nothing new; in fact, sanctions themselves depend on this sort of action.

Sanctions originated in the early 20th century, when international law was very different from what it is today. The Great Powers controlled the development of the international legal order, which supported colonial empires and upheld racial inequality, and sovereignty was a prerogative of European and American states. Most of Latin America, Africa, and Asia was considered only partially sovereign at best, and “uncivilized” at worst.

American politicians and elites in this period were strong proponents of international law: Theodore Roosevelt, Howard Taft, and Andrew Carnegie all championed arbitration to resolve international disputes. They supported pooling Great Power navies as an international police force against recalcitrant countries. This entire operation was deeply colonial. Gunboats and expeditionary forces could be used to impose imperial discipline by force—a “sanction” to protect Western investments and citizens abroad. International law gave the Great Powers this right to the use of force, since colonies and non-Western states were not fully sovereign.

Decolonization between the 1940s and the 1970s changed that. The end of formal empire enabled many colonial peoples to acquire sovereign statehood. As more countries gained a say in which global norms should be enforced, using economic and diplomatic pressure acquired greater legitimacy. Sanctions could now be used against colonizers, such as the white-settler regimes in Rhodesia and apartheid South Africa. The United Nations General Assembly became the Third World’s favored vehicle for advocating the equal application of international norms to all. Broad member-state coalitions opposed the illegal use of force and pressed for a new international economic order.

During the Cold War, this activism made the United States distrustful of the General Assembly and of international legal institutions. The core principle of territorial integrity adopted in the UN Charter protected governments that Washington opposed or wanted to overthrow. Over time, the United States began to undercut international law in several ways: It undertook covert operations, used sanctions unilaterally, and controversially expanded the right to self-defense. Nixon, for instance, reinterpreted the meaning of self-defense to justify invading Cambodia and bombing Laos in 1969 and 1970. The Reagan administration unlawfully invoked self-defense in the 1980s to invade Grenada and Panama, bomb Libya, and mine the coastal waters of Nicaragua. In the latter case, the International Court of Justice (ICJ) issued a landmark verdict that found the United States guilty of illegal interference and use of force against a sovereign state; the ICJ’s 1986 Nicaragua v. United States ruling angered officials in Washington, DC, and was the context in which neoconservatives such as John Bolton cut their teeth. In a world where American adversaries were fully sovereign, Bolton and other unilateralists saw international law as a threat to US national security.

The end of the Cold War reduced the tensions between Washington’s power and the international rule of law. During the 1990s, international outrage at atrocities in Yugoslavia and Rwanda produced special war-crimes tribunals and spurred the emergence of the field of international criminal law. Unlike the inter-state disputes governed by traditional international law, international criminal law punishes individuals, not states, that are responsible for war crimes, crimes against humanity, and genocide. The Rome Statute of 1998, which created the International Criminal Court (ICC) and to which 120 states became parties, was a major advance in this domain.

Because of its wide jurisdiction, major powers have resisted the ICC. China and India never signed the Rome Statute. Russia and Israel signed but did not ratify the treaty, and then retracted their signature. In spite of President Bill Clinton’s initial support and adherence, Congress never ratified the statute, either—a position defended by Bolton and his ilk, who called the ICC “a stealth approach to eroding constitutionalism.” The Bush administration formally rejected the court in May 2002. The neoconservative attack on international law included the passage that year of the American Service-Members’ Protection Act. Informally known as the Hague Invasion Act, it allows the use of military force to free Americans or citizens of countries the United States considers allies held by the ICC in the Hague.

The ICC has been seriously criticized from the left as a biased institution, and there’s some truth to that: In its first decade, the court only investigated and prosecuted war criminals from African countries. This made it vulnerable to accusations that it was an instrument of neocolonialism—a return to the times when non-Western states were not fully sovereign, and international law was a tool of imperial domination. Bolton’s crusade against The Hague acquired unexpected support from African states such as Burundi, which became the first state to leave the court in October 2017 because it opposed probes about alleged crimes against humanity during its 2015 elections (the ICC has continued to investigate the case).

But in recent years the ICC has begun to change. In 2012, the Gambian lawyer Fatou Bensouda took charge. She has started investigations of crimes committed in many different contexts: the Colombian civil war, the murderous war on drugs in the Philippines, Israel’s occupation of Palestinian territories, Myanmar’s repression of the Rohingya, Ukrainian crackdowns on the Maidan protesters, the UK occupation of Iraq, and the US war in Afghanistan. The ICC has acquitted several African government officials charged with atrocities. It recently bungled a recent case involving the Congolese politician Jean-Pierre Bemba. This is evidence that its prosecution leaves much to be desired, but also refutes the charge that it biased against African nations and that its trials are rigged.

More ambitiously, Bensouda is scrutinizing not only state officials but also corporations and civil-society actors. In 2016 she indicated that the ICC aims to create a “complementary system of criminal justice” in which the court helps countries prosecuting “the illegal exploitation of natural resources, arms trafficking, human trafficking, terrorism, financial crimes, land grabbing or the destruction of the environment.”

International law is currently under serious pressure, and progressive foreign policy should take an interest in improving it. Russia illegally annexed the Crimea in 2014 and has defied economic sanctions imposed in response, and the Trump administration has reprised an American Cold War tradition of unilateral hostility to international norms. The challenge is how to protect weaker states and peoples from domination while preventing the abuse of sovereignty to cover up domestic atrocities or justify illegal war.

Bensouda’s attempt to broaden the reach of international criminal law through the ICC is important, but it can only be one part of a more complex, multi-layered progressive project. In the realm of global trade and investment law, for example, sovereign decision-making actually needs to be strengthened. The economic content of the rules-based global order facilitates oligarchic self-enrichment and tax avoidance on an enormous scale. In such circumstances, the idea of a rule of law is meaningless unless it promotes accountability, peace, and greater material equality.

That international law can advance a progressive foreign-policy agenda was driven home last month, when the International Court of Justice ruled that Britain must return the Chagos Archipelago, administered as the British Indian Ocean Territory, to Mauritius. The UK government deported the native population and leased the islands to the United States in 1966. Since 2001, the military base on Diego Garcia has become instrumental in Washington’s endless wars in the Greater Middle East, serving as an interrogation site for the CIA and as a staging point for air strikes on Afghanistan. But since the Chagos islands were never properly decolonized and are, in fact, Mauritian sovereign territory, the US presence on Diego Garcia will have to be renegotiated. In different ways, the ICJ and ICC are both putting pressure on the illegal excesses of US hegemony.

In his recent book The Trump Administration and International Law, Obama’s legal adviser to the State Department, Harold Koh, takes the current occupants of the White House to task for their disregard of international law—a criticism enthusiastically endorsed with blurbs from Hillary Clinton, Madeleine Albright, Samantha Power, John Brennan, and Michael Ignatieff. Yet the Obama administration largely ignored its predecessors’ legal transgressions. Bush-era torturers were never held to account, nor was the ridiculous Hague Invasion Act repealed.

In some areas, liberal internationalists even exploited earlier erosions. Obama continued drone strikes by significantly stretching what constituted an “‘imminent threat” justifying self-defense; this has turned out to be a gift to Trump, who has ramped up drone strikes enormously during his first two years in office. Koh himself has opposed the 2010 Kampala Amendments, a set of new rules that give the ICC powers to prosecute the crime of aggression, in part because they curtail Washington’s ability to launch humanitarian interventions. Indeed, strengthening these rules in a substantive sense will not just restrain individual US presidents but impose limits on the exercise of American power in general.

Prosecutions cannot replace politics. International indictments are insufficient in themselves to solve conflicts and improve life in far-flung countries. But holding a far wider range of actors accountable will certainly strengthen the legitimacy of international institutions, and assist grassroots campaigns for political and social justice.

Pompeo’s travel bans against the ICC put its personnel in the same position as foreign citizens affected by the Trump administration’s odious Muslim ban, and given the administration’s radical sovereigntist stance, it is not surprising that it treats institutions seeking accountability for its wars in a similar way. The only way out is to make the rule of international law apply to all governments—including the self-appointed defenders of a “rules-based” global order.