There was a time, not so long ago when many viewed gray zone aggression as a marginal concern. Even those who paid attention to it mostly focused on cyber aggression and disinformation campaigns.

Now, it has become much more serious because we haven’t managed to deter it. Examples of hostile activity by the authoritarian axis of Russia, China, Iran, and North Korea are proliferating.

The UK faces “state-backed sabotage and assassination plots, against the backdrop of a major European land war,” MI5’s Director-General, Ken McCallum, warned on October 8. The same is true for every Western country. Defending free societies against it remains extremely difficult. But Western countries are not defenseless — or rather, they don’t have to be.

As early as 2018, when I launched RUSI’s Modern Deterrence initiative to focus on deterrence of grayzone attacks, it was clear that authoritarian states had (rightly) concluded that using aggression below the threshold of armed military violence was a cheap and effective way of hurting Western societies. 

China was harming Western countries through systematic theft of intellectual property, which had helped the country advance to Western rivals’ innovation standards — and thus economic power — in record time. Russia was engaging in gradual border alternations. Iran was attacking and sometimes assassinating diaspora members living in Western societies. North Korea was subverting the global maritime system by using shadow vessels for deliveries of sanctioned goods. 

These and other gray zone activities, though, were relatively limited and could have been contained if Western countries had taken them seriously – and if they had seriously tried to build appropriate defenses and deterrence. 

Granted, deterring malign activities that can appear anywhere, anytime, and in any guise is extremely difficult, and deterring them without resorting to illegal means or escalating the situation is even harder. A Western country can’t threaten to take a sliver of Russian territory in response to prospective gradual border alterations by the Kremlin. Deterring gray zone aggression is, in fact, so difficult that I called my book about the subject The Defender’s Dilemma.

In his October 8 speech, McCallum observed that even though terrorism remains a significant threat to the UK and other Western countries, state-sponsored malign activity is growing fast. Hostile state “targets include sensitive government information, our technology, our democracy, journalists and defenders of human rights,” he said, and added that, “in just the last year the number of state threat investigations we’re running has shot up by 48%”

Over the past three years, Belarus’s weaponization of migration along its borders with Poland, Latvia, and Lithuania has caused such harm that earlier this month, Poland won EU approval for its plan to suspend asylum for anyone crossing its borders from Belarus. China, Russia, and Iran have intensified their hostage diplomacy, which is why the Merchant of Death, Viktor Bout, is once again a free man and appears to have returned to arms trading. Iran has increased its attacks on members of the diaspora living in the West and is increasingly subcontracting to criminal gangs in Western countries. This summer, Finland saw a string of break-in attempts at water plants, and earlier this month, a Swedish water plant was broken into

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It doesn’t stop there. As I have noted in previous articles for CEPA, in recent weeks, a string of packages containing incendiary devices have been dispatched to German logistics firms. Had everything gone according to the perpetrators’ plans, the packages would have exploded mid-air. This summer, a similar package caught fire at a DHL warehouse in the UK. 

Someone, who seems to be operating from Russian-occupied Ukraine, has been sending bomb threats to enormous numbers of Czech schools. There has been an assassination plot against a German defense company CEO, and Swedish defense firms report a rise in sabotage. 

China continues its maritime harassment of Philippine vessels in the South China Sea. Chinese vessels have cut the two communications cables connecting the Matsu Islands with Taiwan proper, and another Chinese-owned vessel has damaged a pipeline and two undersea cables in the Baltic Sea. (China says the latter was an accident.) A slew of other activities have also been credibly linked to hostile governments.

Grayzone activities are intensifying because the perpetrators know they can get away with them. Because we are open societies, we’re vulnerable to all manner of interference, and because we still haven’t managed to stand up an effective defense against gray zone aggression, let alone deterrence of it, the cost of using it remains ridiculously low. For that reason, the list of states engaging in gray zone aggression is likely to grow. 

So is the harm such countries cause our societies. Credit to Ken McCallum for being transparent with the British public about the “state-backed sabotage and assassination plots” facing the country. Credit, too, to the Swedish Security Police for telling the public about the Russian sabotage and malign-influence efforts taking place. And credit to the heads of Germany’s three intelligence agencies, who, in a news conference earlier in October, told the public about Russian espionage and sabotage that have increased “both quantitatively and qualitatively” and reached a “previously unknown” level.

Educating the public about the astonishing extent of gray zone aggression against our countries is, in fact, crucial if we are to blunt the harm of this aggression because an informed public can help spot things that don’t look right. And for that to happen, citizens need to know roughly what to look for.

The decisive change to hostile states’ harmful activities, though, will come when we punish them for it. That extremely hard part is at the core of the defender’s dilemma. 

But let’s begin right away, with the somewhat easier task of shoring up societal resilience. Every bit helps in the fight against the torrent of gray zone aggression.

Elisabeth Braw is a Senior Fellow at the Atlantic Council.

Europe’s Edge is CEPA’s online journal covering critical topics on the foreign policy docket across Europe and North America. All opinions expressed on Europe’s Edge are those of the author alone and may not represent those of the institutions they represent or the Center for European Policy Analysis. CEPA maintains a strict intellectual independence policy across all its projects and publications.

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CEPA’s online journal covering critical topics on the foreign policy docket across Europe and North America.
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