Vladimir Putin’s invasion of Ukraine has turned much of the world against Russia. But one country stands out for its vocal support of Moscow, and for its role as Russia’s main accomplice in the war. Belarus not only served as a staging ground for Russian troops as they prepared to invade Ukraine but allowed Russian missiles to be fired from its soil and opened its hospitals to Russian soldiers injured in combat. Now there are signs that Belarus could become directly involved in the war: Belarusian troops appear to be readying for deployment, and U.S. and NATO officials have warned that they could cross into Ukraine in a matter of days.

Having failed to deter Russia from attacking Ukraine, the United States and its allies must urgently consider how to prevent Belarus from becoming a full belligerent in the war. A Belarusian invasion is not a foregone conclusion. Russia claims that it is now focused on gaining control of the Donbas, in the east of Ukraine and far from the border with Belarus, but it is unclear if that is really true or if Moscow is simply regrouping for future operations. Unless Western nations impose harsher sanctions on Belarus, position additional NATO troops along the country’s western border as a deterrent, and offer Minsk a diplomatic off-ramp, Belarusian troops may soon be fighting alongside their Russian counterparts in Ukraine.


In response to Russia’s aggression in Ukraine, Western nations imposed a harsh suite of sanctions on Moscow, freezing the assets of its central bank, barring many of its biggest banks from transacting in dollars, and banning or restricting imports of Russian oil and gas. But these measures came too late—only after Russia had launched its invasion. The West cannot afford to be as reactive with Belarus as it was with Russia, hoping for restraint where none has been demonstrated.

The United States has already sanctioned Belarusian President Alexander Lukashenko and members of his family over human rights abuses related to the war, adding to sanctions imposed last year over Lukashenko’s crackdown on peaceful protests, and restricted the export of luxury goods to Belarus. The United States and the European Union have also restricted the ability of some Belarusian banks to use the SWIFT network, which serves as the backbone of the international payments system. But Western nations have so far refrained from imposing the much harsher sanctions they have imposed on Russia. To deter Belarus from becoming directly involved in the war, they must strengthen and expand the punitive measures against Minsk. Additional targeted sanctions against Belarusian officials, full blocking sanctions on numerous Belarusian financial institutions, more export controls, and sanctions on trade would send a much stronger deterrent signal.

In addition to imposing tougher sanctions, the United States and its allies must communicate clearly that Belarus will face even harsher consequences if it proceeds with an invasion. Belarus deserves condemnation for its role in the war so far, but it may not yet have breached the United Nations Charter or other international legal prohibitions against the use of force. There is therefore room for the country to redeem itself. Belarus is not Russia. It has no nuclear weapons and its conventional forces are weak. Fighting alongside the Russian military, however, Belarusian troops have the ability to inflict additional pain on the Ukrainian people.

Belarus deserves condemnation for its role in the war, but there is room for the country to redeem itself.

In calibrating its threats against Belarus, the West should not treat the country as an extension of Russia. Rather, it should consider the commitments that Russia and Belarus have made to each other—and use them to divide the two allies to the extent possible. Belarus is a member of the Collective Security Treaty Organization, Russia’s version of NATO. Like NATO members, CTSO members are obliged to consider an attack against one an attack against all. But it remains unclear how much stock to put in CTSO commitments for mutual defense. During the recent Nagorno-Karabakh war, for instance, Russia did not defend Armenia, its CTSO partner, against Azerbaijan. Whether Russia would defend Belarus is even less certain, especially now that it is stretched thin as a result of its assault on Ukraine. Moscow has limited conventional capability to engage NATO. And while it would almost certainly defend itself against a direct attack by U.S. or NATO forces, it may not be willing to defend Belarus or Belarusian forces and risk a broader escalation of the conflict.

The United States and its allies should use this uncertainty to their advantage. NATO should increase its presence on Belarus’s western border, conducting televised military maneuvers, unit training, and live fires. Such a show of force may make Lukashenko think twice about provoking a NATO attack that he would be on his own to defend against. After all, he does not have the forces to defend his NATO frontier, quell domestic dissent, and invade Ukraine. Such a course of action would not be without risks. But NATO members can mitigate the risk of inviting further Russian escalation by clearly communicating that they will target Belarusian forces only if force becomes necessary. This would likely allow them to thread the needle between deterring Belarus and provoking Moscow.

The United States and other NATO countries could legally justify such assertive military steps under Article 51 of the UN Charter, which allows member states to defend themselves or other members from attack, so long as the UN Security Council does not take action to the contrary. And of course, the Security Council will not take action—for the same reason it took no meaningful action after Russia invaded Ukraine. NATO countries could also seek a symbolic, non-binding resolution from the UN General Assembly that condemns Belarusian aggression and supports their defensive actions.

Finally, the United States and its allies must provide Lukashenko with a diplomatic off-ramp. As long as Belarus remains on the sidelines, NATO should assure Belarusian leaders both publicly and privately that their country will not be attacked. If Belarus is willing to go further and end its support for Russia’s invasion, the West could offer to eventually lift some of the newly imposed sanctions.


The United States and its allies failed to deter Russia’s invasion of Ukraine, but now they have an opportunity for a do-over with Belarus. Using economic, military, and diplomatic means, they can raise the costs of Belarusian aggression while minimizing the risk of a dangerous escalation. But they must act swiftly. The longer the conflict continues—and the more countries become embroiled in it—the greater the risk that the United States and NATO will be drawn in, as well.

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  • YEVGENY VINDMAN is a Colonel in the U.S. Army JAG Corps who served as Deputy Legal Adviser on the National Security Council from 2018 to 2020.
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