putin candle
© Mikhail Metzel / POOL / SputnikRussian President Vladimir Putin lights a candle to commemorate victims of a terrorist attack on the Crocus City Hall concert venue on the day of national mourning, in Russia.
Russian foreign policy could change significantly, depending on the results of the investigation into the atrocity.

The heinous act of terrorism at the Crocus City Hall concert venue just outside Moscow on Friday night - which is confirmed to have killed more than 130 people at the time of writing - has perhaps shaken Russia more than anything since a similar attack on a theater in the capital in 2002.

This latest atrocity will certainly have a major impact on the Russian people's consciousness and the nation's public security. It could also lead to serious changes in Moscow's foreign policy, depending on the results of the investigation into the source of the attack and its masterminds. Considering the enormously high stakes involved in its findings and conclusions, there is no doubt that the investigation will have to be incredibly thorough.

The US government's version of an Islamic State connection to the attack has been met with skepticism by Russian officials and commentators. Firstly, they were surprised by how quickly - virtually within minutes - Washington pointed the finger at the group. What also drew the attention of Russian observers was the US reference to an IS-linked news site which had claimed responsibility for the crime. Normally, all such sources are subjected to thorough checks. But not this time. Figures in Russia have also noted that American spokesmen immediately, and without prompting, declared that Ukraine was in no way linked to the act of terror.

Other criticisms of the American version include the style of the attack (no political statements or demands were made); the admission by one of the captured attackers that he had shot innocent people for money; and the fact that this was not planned as a suicide operation. Many experts have pointed out that IS is far from its prime, and that Russian forces defeated its core elements in Syria years ago. This has allowed speculation to grow about a false flag attack.

Ukraine, true to form, and alone among the nations of the world, has suggested that the Crocus City atrocity was an operation carried out by Russia's own secret services, launched to facilitate a further tightening of the political regime and a new wave of mobilization. Clearly nonsensical, this interpretation invoked in many Russian minds the old proverb, "liar, liar, pants on fire."

Russian President Vladimir Putin, in his five-minute address to the nation on Saturday, refrained from rolling out the Kremlin's own version. His words and his demeanor were calm, but the style of his remarks was stern. Those behind the attack "will be punished whoever they are and wherever they may be," the president declared. The direction of Putin's thinking was revealed by the two facts - not conjectures - he raised: that the terrorists, having fled the scene of the assault, had been apprehended not far (100km or so) from the Ukrainian border, and that "information" had been obtained that they intended to cross the border into Ukraine, where "they had contacts."

At this point, nothing is firmly established. The results of the Russian investigation will be enormously important. If Moscow concludes that the attack was conceived, planned, and organized by the Ukrainians - say, the military intelligence agency GUR - Putin's public warning would logically mean that the agency's leaders will not just be "legitimate" targets, but priority ones for Russia. Since an attack of such gravity would almost certainly have required the approval of Ukrainian President Vladimir Zelensky, the "guarantee" that Putin informally gave to foreign leaders (including Israel's then-Prime Minister Naftali Bennett) that Russia would not target Zelensky personally, would presumably be lifted. If so, Moscow would be removing one of its most important self-imposed constraints - not to touch Kiev's senior leadership.

The Crocus City terrorist attack seemingly fits into a pattern. It has come against the background of Ukraine's intensification of artillery and drone strikes against the civilian population in Russian regions on the shared border, as well as attempts (all thwarted, thus far) to raid Russian villages. As a result, scores of Russian civilians have been killed or wounded, and thousands of children evacuated to safety. The conclusion reached by many analysts is that Ukraine, by focusing on "soft" civilian targets, had been seeking to undermine the Russian population's morale in the run-up to the presidential elections in mid-March, and to strain the country's internal stability after them.

Regarding the concert hall massacre, there is another aspect at play: the US version of IS complicity and the use of Tajik citizens to carry out the attack may be intended to stoke inter-ethnic tensions within Russia between the Slavic majority and the Muslim minority population, both local and immigrant.

Taken together, all of this strengthens the argument of those inside Russia who have long insisted that Ukraine - under its present ultranationalist leadership - is a terrorist state, and that Russia simply cannot tolerate such a regime on its borders. They believe that any talk of a ceasefire or negotiations should stop. Russia must achieve a complete victory - otherwise it will constantly bleed at the hands of the terrorists in power next door, supported and protected by the country's adversaries in the West. If the results of the investigation confirm that Ukraine was behind the Crocus City massacre, Russia's war aims will need to be greatly expanded, and the conflict will significantly grow in intensity.

One thing that's important to note: The war in Ukraine is not considered by Russians to be a war against Ukraine.

Rather, it is seen as a fight against the US-led West, which is using Ukraine as a battering ram to inflict a "strategic defeat" on Russia. It is interesting that Kremlin spokesman Dmitry Peskov just last week publicly admitted for the first time that the "special military operation" was in fact now a war. It became so, he said, as a result of the West's involvement in the conflict.

Thus, if Ukraine's complicity in Friday's terrorist attack is indeed established, it would also suggest, at a minimum, US knowledge and de facto approval of it. In this respect, various people have already highlighted the recent warnings by the GUR chief, Kirill Budanov, and outgoing US Undersecretary of State Victoria Nuland about "unpleasant surprises" awaiting Russia in the near future.

As a result, Russia's own warnings about striking airfields in NATO countries if they are used by the Ukrainian Air Force, and about wiping out French (or any other NATO) troop contingents if they are sent into Ukraine, are acquiring more credibility. Escalation of the conflict, which heretofore has mostly been driven by Western actions, each time raising the stakes a notch, and Russia (in)famously "exercising restraint," will potentially lead to a head-on collision.

Unless, of course, Washington decides at some point that enough is enough, that what's happening is too dangerous, and that, unlike for Russia, the battle in Ukraine is not existential for the US itself - or even for its dominant position in Europe.

By Dmitry Trenin, a research professor at the Higher School of Economics and a lead research fellow at the Institute of World Economy and International Relations. He is also a member of the Russian International Affairs Council (RIAC).