Önder Özar Diplomasi Sevgisi: BROOKINGS Commentary - December 17, 2025 - Can sanctions change the course of conflict?

BROOKINGS

Commentary

Can sanctions change the course of conflict?

Scott R. Anderson, Pavel K. Baev, Robin Brooks, Samantha Gross,

Samantha Gross, Fellow, Cross-Brookings Initiative on Energy and Climate, The Brookings Institution

Samantha Gross

Director - Energy Security and Climate Initiative, Fellow - Foreign Policy, Energy Security and Climate Initiative

Ben Harris, Daniel S. Hamilton, Kari Heerman, and Suzanne Maloney

December 17, 2025

Sections

Brooks and Harris: Sanctions pressure revenues

Maloney: Sanctions are no silver bullet

Baev: Sanctions challenge recruitment

Hamilton: Sanctions' success depends on context

Gross: Enforcement is key

Anderson: Major power conflict needs smarter sanctions

Heerman: Effective sanctions anticipate evasion

Sanctions have long been an important component of the foreign relations toolkit, but the global landscape in which they operate is changing. The response to Russia’s war in Ukraine has involved a complex set of economic statecraft measures—spanning energy, finance, and export controls—and has highlighted both the power and the limits of sanctions in an era of major-power competition and rapid technological change. In this piece, Brookings experts weigh in on how sanctions are being used today, what their effects have been, and how shifts in geopolitics and global markets are shaping their future. In short: Can sanctions change the course of conflict?

For more expert analyses on the efficacy of sanctions, watch this recent Brookings event.

Robin Brooks and Ben Harris

Oil market sanctions are pressuring Russia’s revenues

Sanctions can undoubtedly disrupt an economy. Consider the array of sanctions levied against the Russian oil trade in response to its illegal invasion of Ukraine. These actions substantially lowered the profitability of Russia’s export of crude oil and refined petroleum products, reducing the associated government revenues in the process. Whether these and other sanctions changed the course of the conflict is unknowable, but it is without question that sanctions can impose higher costs on countries that violate international law.

The key Western energy sanctions against Russia are an EU ban on the import of seaborne Russian oil and the imposition of price caps on all transactions involving Russian oil that use G7-based services such as insurance or financing. The U.S. Treasury Department’s January 2025 order to sanction 183 Russian vessels and October 2025 ban on trading with major Russian energy companies Rosneft and Lukoil were also significant moves against Russia. The EU import ban dramatically reshaped trading routes for Russian oil, shifting export destinations away from Europe and toward Asia—with a notable rise in transportation costs. More importantly, these various actions appear to have preserved an unprecedented spread between the market price of oil and the price received by Russia for its exports, starkly lowering Russian revenue.

As shown in the chart below, immediately following the invasion of Ukraine the Urals oil price (Russia’s main oil benchmark) fell sharply relative to the market price (represented by the Brent global benchmark). This spread remained high until Russia began amassing a “shadow fleet” of oil tankers and then rose again towards the end of 2023 as the U.S. began to sanction individual tankers. Importantly, too, this sanctioning of shadow fleet tankers by the U.S. Treasury’s Office of Foreign Assets Control (OFAC) appears to have had a negative effect on export volumes.

Figure 1a

Brent and Urals oil price, in $ per barrel

2019

2020

2021

2022

2023

2024

2025

100

$120

UralsMar ’23$49.70

Russian invasion of Ukraine

Price cap announced

Shadow fleet

buildup

Rosneft and Lukoil sanctions

announced

BrentUrals

Source: Haver Analytics

The Brookings Institution

While these measures have been effective in preserving the oil price spread and thus curbing Russia’s oil revenues, Russia’s deployment of its shadow fleet demands further countermeasures. These should include additional tanker sanctions by OFAC and increased pressure on flag states to comply with maritime law—namely by requiring that ships flying their flags carry adequate insurance. These additional steps will weaken the shadow fleet and force Russia to comply with the terms of the price cap.

Suzanne Maloney

Sanctions are no silver bullet

Sanctions have long had an important place in the American toolkit for addressing national security threats. However, their track record in achieving the most ambitious policy outcomes—such as conflict resolution—is decidedly mixed. The long history and vast labyrinth of American and international measures targeting Iran illustrates both the opportunities and the limitations of sanctions.

The 1979 seizure of the U.S. Embassy in Tehran prompted the first use of the International Emergency Economic Powers Act (IEEPA) to freeze all Iranian state assets held in U.S. financial institutions. That step, together with a ban on U.S. imports of Iranian oil and an embargo on U.S. weapons and military spare parts, ultimately forced Tehran to negotiate and free the American hostages after 14 months.

The 2015 Iran nuclear deal is another example of sanctions’ success. Beginning in 2006, Washington pioneered new measures that progressively constricted Iran’s access to the international financial system and used that leverage to decrease global imports of Iranian oil. Iranian leaders acknowledged the key role of economic imperatives in their decision to accept restrictions on their nuclear program after years of resistance to any compromise.

But these few breakthroughs punctuated decades of economic coercion, with ultimately limited effect on generating a durable end of Tehran’s threats to its neighbors or its citizens. The long history of sanctioning Iran has repeatedly exposed that these measures are no silver bullet: They present challenges to reverse, inspire creative adaptation and circumvention, instigate unintended consequences for U.S. interests, and wreak collateral damage on vulnerable societies. And the rare successes have not proven replicable for other crises. Today, Iranians are enduring a second round of the Trump administration’s ”maximum pressure” sanctions, with the costs borne mostly by the ordinary Iranians who are least able to affect the outcome of their government’s standoff with Washington.

Pavel Baev

Sanctions are squeezing Russia’s recruitment model

Military analysts tend to view the impact of sanctions as irrelevant to the course of combat operations, but they may now find economists’ assessments useful, as each round of tightening of the U.S. and the EU sanction regimes provides new data on the unique experiment in curtailing the trade and investment flows of a major world power. What makes these sustained and expanding Western efforts to punish the aggressor relevant to analyzing the progress of battles that are both static and fluid is Russia’s own experiment in compensating for heavy military casualties not through traditional mobilization but through paid recruitment. Launched after the turmoil in Russian society caused by the partial mobilization in autumn 2022, this experiment delivered results the high command deemed satisfactory over the next three years of the war of attrition. Regional authorities responsible for producing the required manpower have managed to fulfil this task by offering contract-signing bonuses many times larger than annual salaries. But the deepening crisis in state finances is cutting this “generosity” short, as the large federal budget deficit has led to severe reductions of transfers to regional budgets. Every measure aimed at curtailing Russia’s oil export revenues aggravates the funding shortage and changes the parameters of the recruitment experiment, which could suddenly collapse.

Dan Hamilton

Sanctions' success depends on context

Sanctions can alter the course of conflict under certain circumstances. They are particularly effective if imposed by a broad coalition and as part of a wider array of policy actions, ranging from diplomatic pressure to military coercion. For instance, Iran negotiated limits on its nuclear program in 2015 under pressure of international sanctions. Libya abandoned its nuclear program in 2003 in the face of a concerted international campaign of sanctions, diplomatic pressure, and security assurances. South Africa’s apartheid regime buckled in the early 1990s under the weight of determined domestic resistance, supported by international sanctions, arms embargoes, and cultural boycotts. There are many other examples.

The mere threat of sanctions can also have an effect. President George H.W. Bush’s delay of $3 billion in loan guarantees in 1991 pushed Israel to join the Madrid Peace Conference. President Eisenhower’s threat to block IMF loans to Great Britain and to withdraw U.S. support for the pound sterling in 1956, together with international condemnation, compelled the U.K., France, and Israel to end their war against Egypt. The League of Nations used sanctions threats to defuse a Yugoslav-Albanian conflict in 1921 and a Greece-Bulgaria dispute in 1925.

International sanctions have not forced Russia to stop its war against Ukraine, but they have changed the course of the conflict by weakening the Russian economy and making it harder for Moscow to advance its aggressive plans. Tighter sanctions would impose even higher costs.

There are of course countless cases where sanctions have had no effect. One should neither exaggerate their effectiveness nor doubt their occasional utility.

Samantha Gross

Enforcement is key to making oil sanctions work

Sanctions on Russian energy products are intended to make the war in Ukraine more painful for Moscow, forcing it to re-think its aggressions. This focus makes sense, as oil and gas revenues have made up 30 to 50% of Russian federal government revenues over the last decade. However, the West has been playing a game of cat and mouse with Russia. The West tries new strategies and the Russians find ways around them. That seems likely to continue.

The oil price cap, which entered into force in December 2022, was intended to reduce revenues from Russian oil exports without removing them from the market. But the Russians turned to a “shadow fleet” of tankers with obfuscated ownership and without Western insurance to get around the price cap. New sanctions prevent U.S. companies from doing business with Rosneft or Lukoil, who together make up about half of Russia’s oil production. Secondary sanctions allow the U.S. to block access to its financial system for non-U.S. entities that do business with the two companies. This is a much stricter regime on paper, enabled by a supply glut in global oil markets. But enforcement is the key to success.

The most important question is whether the U.S. will force China to comply. In the first 10 months of 2025, China imported an average of 2 million barrels per day of Russian crude oil, compared to total imports of around 11 million barrels per day. The Trump administration has many issues in its relationship with China, including ensuring access to rare earth materials and keeping trade negotiations open. China and Russia will undoubtedly try to push the envelope on sanctions—how will the Trump administration react? Chinese imports from Russia have dropped recently, but some inefficient Chinese refineries rely on discounted oil, often from sanctioned countries, for their survival. President Trump did not discuss oil sanctions in his meeting with Chinese President Xi during their meeting on October 30, an ominous sign for the sanctions’ effectiveness.

Scott R. Anderson

Addressing major power conflict requires smart(er) sanctions

Economic (and particularly financial) sanctions have proven to be an effective tool for addressing the sorts of asymmetric threats—terrorism, transnational crime, rogue states—that have dominated post-Cold War policy concerns. But the same may not be true of the very different challenges presented by the emerging era of major power competition.

The focus on asymmetric threats has contributed to several pathologies in sanctions policies, particularly in the United States. The ease with which economic sanctions can be imposed on foreign targets has made them a foreign policy tool of first resort, resulting in overbroad application. As sanctioned entities are often highly stigmatized, there is little incentive to reconsider sanctions once imposed. By identifying sanctioned entities without clarifying permitted activities, conventional list-based sanction regimes contribute to excess de-risking by the private sector. Similarly, as financial institutions are unlikely to favor business with sanctioned entities over the U.S. economy, enforcement is administratively easy. Even unilateral sanctions can have high rates of compliance, limiting the incentive for multilateral cooperation.

These tendencies cause problems, however, when sanctions target entities with their own substantial economic power, like other major powers. Cutting economic relations with such targets can be costly for both private sector entities and the broader global economy, requiring more tailored application. Some private actors may be more willing to risk sanctions penalties to avoid disengagement—especially if the targeted entity has developed strategies for evading sanctions, as China and Russia have. By increasing the perceived cost of compliance, excess derisking can also increase the risk of private sector defection. Even where it does not, it can amplify sanctions’ effects in unintended and counterproductive ways. And because of the relative parity in economic power, unilateral sanctions are far less likely to be effective than multilateral ones.

Adapting to the new challenges of major power competition means addressing these pathologies. Application should be selective and targeted, while periodic review should facilitate removal and provide an incentive to return to compliance. Sanctions lists should incorporate both restricted entities and permissive licenses with relative parity in order to limit the inclination towards excess derisking. Investments need to be made in agencies that monitor for and enforce compliance. And states need to align their standards of evidence, procedural protections, and domestic legal authorities to facilitate easier multilateral application outside of the U.N. system, which is likely to be hamstrung by Chinese and Russian vetoes.

To its credit, the Biden administration anticipated many of these issue in a 2021 strategic review and made some progress, most notably in the context of excess derisking and humanitarian relief. But the Trump administration has since moved in the wrong direction, including by wielding sanctions capriciously, weakening relevant agencies, and alienating key allies. That said, its adept handling of sanctions on post-Assad Syria suggests some appreciation for the complex policy tradeoffs sanctions can entail in this new era of geopolitics. Whether this will ultimately lead it to change tack remains to be seen.

Kari Heerman

Effective sanctions anticipate and address evasion

Sanctions rarely determine the outcome of a conflict outright, but they can meaningfully alter its course by imposing costs, creating friction, and constraining an aggressor’s options. These constraints matter even when evasion occurs. Evasion may shift how pressure is felt, but it does not erase it; even forcing an aggressor to work through costlier or riskier channels can hinder its ability to sustain conflict. Policymakers will have to get used to this reality: Evasion is inevitable and will become easier as technology advances and China chooses to provide viable economic and logistical alternatives. What matters is responding with the right tools.

Evasion follows two subtly distinct pathways. Circumvention is the more familiar form: The illegal acquisition of restricted goods or financial flows from jurisdictions that are, in principle, part of a sanctions regime. In the war in Ukraine, Russia has gained access to export-controlled goods that sanctioning governments intended to restrict through a range of illicit channels. Because this activity occurs within the coalition’s jurisdiction, circumvention is an enforcement issue. Governments have responded by tightening export controls, sharing information, and strengthening compliance accordingly.

Avoidance, by contrast, operates outside the sanctioning government’s reach. It is a manifestation of trade diversion—a core concept in international trade theory. In the sanctions context, as the cost of accessing restricted goods or financial channels from compliant partners rises, targeted actors reroute activity to states, firms, or networks willing to serve as substitutes. These channels are less efficient, more opaque, or more expensive, meaning that even successful avoidance still imposes costs and frictions on the sanctioned actor. Russia’s “shadow fleet” of tankers and its pivot to renminbi-denominated financing fit this pattern.

Avoidance arises not from gaps in enforcement but from the availability of external alternatives, making it a fundamentally geopolitical and technological challenge. The presence of large economies outside the sanctions coalition, the strategic choices of hedging states, and the incentives of commercial actors shape the degree to which avoidance is viable. Today, technologies such as cryptocurrencies and China’s willingness to serve as an alternative economic partner are dramatically expanding these possibilities. These shifts mean avoidance will increasingly erode sanctions’ leverage unless policymakers use diplomacy and broader strategic choices to close off these pathways.

Ultimately, policymakers must recognize when sanctions are weakened by circumvention, which enforcement can constrain, and when they are weakened by avoidance, which signals a broader strategic challenge. Treating all evasion as an enforcement problem will lead the U.S. to over-invest in legal remedies and under-invest in the diplomatic and geopolitical tools needed to shape the environment in which avoidance occurs. Sanctions will retain their power only if policymakers adapt to this reality.

Önder Özar Diplomasi Sevgisi

Thursday, December 18, 2025

BROOKINGS Commentary - December 17, 2025 - Can sanctions change the course of conflict?

No comments:

Post a Comment