Kerry Buck is a former Canadian ambassador to NATO.
When Russia invaded Ukraine in February, Vladimir Putin threatened anyone who tried to stop him with consequences “such as you have never seen in your entire history.” The language was chilling, and a clear nuclear threat, but I thought this was more flexing of muscles than a statement of intent. We have seen leaders in recent years make similar warnings, after all, including when U.S. president Donald Trump in 2017 warned of “fire and fury like the world has never seen” against North Korea. Russia has itself regularly threatened nuclear-weapon use since 2014.
But Mr. Putin’s speech on Sept. 21 was different. This time, he upped the ante by signalling Russia is prepared to use “all the means at [its] disposal” to defend its lands and people, a definition he has dangerously widened to include four “annexed” Ukrainian territories not under complete Russian control. He spoke of the precedent set by the U.S. when it bombed Hiroshima and Nagasaki in Japan in 1945, and added that he was “not bluffing.” And while his announcement of a partial mobilization of troops seemed to indicate that he might first escalate the war using non-nuclear tools, the disastrous response to it – the number of soldiers conscripted has been eclipsed by the number of Russians fleeing the country – suggests he has set a trap of his own making. Forced into a corner, he may now lash out unpredictably.
It wasn’t this way during most of the Cold War. After Nikita Khrushchev infamously banged his shoe on the desk at the United Nations threatening to “bury” the West, and the close call of the Cuban Missile Crisis in 1962, leaders on both sides became more careful. But the nuclear taboo is starting to fray, and while the tactical nuclear weapons Mr. Putin may be considering are smaller than the bombs dropped in 1945, they can still take out whole cities and cause considerable, unpredictable damage.
The problem with nuclear deterrence is it assumes rational calculations. Before the war, most Western analysts, myself included, thought it wasn’t in Russia’s interest to launch the largest ground war in Europe since the Second World War. And yet, as the U.S. expert in Russian affairs Fiona Hill said, “Every time you think, ‘No, he wouldn’t, would he?’ Well, yes, he would.”
The existential threat apparently driving Mr. Putin right now is not to the Russian state, but his own hold on power. The odds are slim of him remaining president if Russia’s conventional forces in Ukraine collapse, or worse, if Ukraine takes back Crimea. A dictator will almost always choose rash military moves over prudence if there is a perceived threat to his own regime.
The first thing that Ukraine and the West must do is further isolate and dissuade Russia. The U.S. has already sent public and private messages that there will be catastrophic consequences if Russia unleashes a nuclear weapon. While that might not trigger NATO’s collective defence principle, Moscow needs to understand that a conventional military response would come from countries beyond the U.S. It must also be clear that any use would make Russia a complete international pariah. Neither China nor India have an interest in seeing the nuclear taboo broken, and Western diplomats have been encouraging countries in the Indo-Pacific and Latin America to distance themselves from Russia. There is still considerable room for shock-and-awe sanctions, too.
The second job is to watch Russia very closely and prepare for a potential attack. In 2014, the world was surprised by Mr. Putin’s sudden move into Crimea; today, monitoring is stronger. Russian tactical nuclear weapons are stored separately from their delivery systems, and any effort to bring the two together to launch them would be more effectively picked up by surveillance. And while there are few checks on the Russian President’s power, intelligence agencies will also be watching for any internal tensions among Russian leaders, particularly among nuclear decision makers. In the meantime, NATO should provide radiological and nuclear-defence equipment to Ukraine and other countries in the region.
In his September speech, Mr. Putin called on Ukraine to return to negotiations. But Ukrainian President Volodymyr Zelensky has said he will not negotiate until Mr. Putin is gone and Ukraine controls all of the annexed territories, including Crimea. While Mr. Zelensky may yet decide to compromise to halt a grinding war, moving to negotiations now would lock in a military and territorial status quo not to Ukraine’s advantage – and worse, it would send the message that nuclear blackmail works. That outcome would be particularly dangerous, since Ukraine gave up its Soviet-era nuclear weaponry in 1994 in exchange for guarantees its borders would be respected.
The West is walking a fine line right now at a very dangerous point, dealing with an unpredictable leader. A non-response by the West to nuclear use would launch a race to rearm and create more global instability. But too aggressive a response, or one that involves nuclear escalation, would run the risk of launching the Third World War. If the world gets through this period unscathed, it will be important to return to predictability – by rebuilding a nuclear taboo that has served us well for seven decades.