What Do We Do if Putin Uses Chemical Weapons?

There are reports that Russia may be planning to use — or, according to unverified reports from local officials in Mariupol, might have already used — chemical weapons as part of its offensive in eastern Ukraine. The Biden administration has already set up a Tiger Team of national security officials to consider options in the event this happens; now is the time for these discussions to become more public.

We’ve traveled this road before, badly. In August 2012, Barack Obama publicly warned the Bashar al-Assad regime in Syria against employing chemical weapons. “A red line for us is we start seeing a whole bunch of chemical weapons moving around or being utilized,” he said. “That would change my calculus.”

It didn’t. The following year, reports emerged that al-Assad had begun using chemical weapons, culminating in a sarin gas attack in a suburb of Damascus. Obama hesitated, fearing a wider war. The British Parliament voted against taking military action in Syria. Congressional Republicans switched overnight from hawkish interventionists to skeptical isolationists. Vladimir Putin intervened with a face-saving offer to get al-Assad to voluntarily divest himself of his chemical arsenal.

The Obama administration crowed that it had achieved the best possible result. But it later came to light that al-Assad had not given up his full arsenal, and he continued to use chlorine gas against his adversaries without consequence. Putin consolidated his alliance with al-Assad, eventually leading to the introduction of Russian forces in Syria in 2015.

And it served as a predicate for Russia’s seizure of Crimea a few months later. Obama’s hesitance in Syria “was decisive,” former President François Hollande of France recently told my colleague Roger Cohen. “Decisive for American credibility, and that had consequences. After that, I believe, Mr. Putin considered Mr. Obama weak.”

This is not a scenario the Biden team can afford to repeat. What should the administration do?

Make only promises it intends to keep. Syria’s use of chemical weapons was a military, humanitarian and international-norms crisis. Obama’s red line turned it into a crisis of American credibility — one whose consequences were much farther-reaching than anything that happened in Syria.

The U.S. response should be asymmetric.President Biden issued a veiled threat to Putin when they met last June in Geneva, by mentioning the ransomware attack on the Colonial Pipeline: “I looked at him. I said, ‘Well, how would you feel if ransomware took on the pipelines from your oil fields?’” That was fair warning.

Bring maximum diplomatic pressure to bear on Germany and other European states to end oil and gas imports from Russia.According to one estimate, those sales provide the Kremlin with $1 billion a day. Berlin remains the weakest link in the effort to create an effective sanctions regime against Russia. This position, craven now, will become morally untenable for Germany if Russia starts gassing Ukrainians. It should lead to the immediate removal of all Russian financial institutions from the SWIFT transaction system to make payments for oil and gas almost impossible.

Tear apart Russia’s supply chains.This is the project of Deputy Treasury Secretary Wally Adeyemo, who has been looking at ways to disrupt the Kremlin’s military supply chains. It should move beyond this to every sector of the Russian economy, by automatically forbidding any company doing business in Russia to also do business in the United States and, hopefully, Europe.

Arm Ukraine with offensive weapons. “If Putin turns out to have used chemical weapons — a favorite M.O. of his, from poisoning political opponents to supporting their use in the Syrian battlefield — the West needs to respond aggressively,” the former NATO commander Adm. James Stavridis wrote me on Tuesday. “Assuming these weapons would be delivered by air, it raises the ante in giving the Ukrainians even more tools to run an effective no-fly zone, including MIG-29 fighters and possibly other platforms and drones with anti-air capability.”

Target Belarus.The Biden administration is leery of direct confrontation with Russia. It should be much less restrained in going after the Kremlin’s puppet regime. Turning off the lights in Minsk for a day would be a useful shot across the bow as the dictator Aleksandr Lukashenko ponders joining the Kremlin’s military effort.

Expect the worst.“He has no compunction against really horrific activity,” another former top American military commander told me about Aleksandr Dvornikov, Russia’s new theater commander. “That’s what he did in Aleppo.” One of the hallmarks of al-Assad’s use of chemical weapons is that he began to use them in discreet ways but grew bolder over time. The effect, the former officer warned, could be a “cumulative Srebrenica,” referring to the 1995 Serb massacre of more than 8,000 Muslim men and boys in Bosnia.

Plan for a long war. Make sure we can provision Ukraine with the weapons it needs for at least a year. Begin to train Ukrainian forces in advanced Western combat systems. Prepare to wall off Russia from the global economy for a decade.

We may not be able to stop Putin from using chemical weapons, but we can still avoid the fatal mistake we made a decade ago with al-Assad.

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