Berlin's Brandenburg Gate is illuminated with the colors of the British flag on March 23 to pay tribute to the victims of an attack in London. (Markus Schreiber/AP)

On March 22, a man used a car and a knife to attack civilians and police officers outside London's Palace of Westminster, the iconic home of the British government. Four people were killed in the incident, which was soon described as a terrorist attack. The perpetrator was fatally shot by police.

The attack prompted a swift outpouring of shock and grief around the world. World leaders rushed to express solidarity with the people of London; just a few hours after the attack, President Trump tweeted his condolences. Meanwhile, international landmarks in Berlin, Paris and Tel Aviv paid homage to the victims of the attack, either by featuring the colors of the British flag or turning off their lights.

Less than two weeks after the London incident, another suspected terrorist attack occurred. On Monday, a bomb went off in a subway car in St. Petersburg. The blast killed at least 14 people and left dozens injured, while new threats and news that another explosive device had been found left Russia's second-largest city on edge.

However, if Russians were hoping for a similar outpouring of international grief, they would have been left disappointed. There were few expressions of solidarity on social media, no popular "#wearestpetersburg” hashtag or tribute images shared. An attack on Russia didn't appear to be held in the same regard as an attack on Britain, even if more people had died.

While some world leaders offered condolences, their responses were more muted than in previous incidents such as the one in London. Even Trump, who rarely misses a chance to tweet promptly in response to terrorist attacks when they are suspected to be inspired by Islamist extremism, kept quiet about the St. Petersburg attack on Twitter. Instead, the White House offered an official readout of Trump's call to Russian President Vladimir Putin. Trump said the attack was a “terrible thing” — but only when asked about it by journalists.

Around the world, there were few visible tributes to the St. Petersburg victims. Berlin's Brandenburg Gate had been illuminated in the colors of the British flag after the London attack. In recent years, the iconic structure also has been lighted up in the colors of the Israeli, Turkish and French flags after terrorist attacks; after the horrific shooting at a gay nightclub in Orlando last year, the landmark had been illuminated in the colors of a rainbow flag.

But the Brandenburg Gate did not commemorate the Russian victims. A city spokesman later told local reporters that only attacks in partner cities or “places with which Berlin has a special relationship” would prompt such an illumination.

Similarly, the Eiffel Tower in Paris had dimmed its lights after the attack in London and made other tributes after other terrorist attacks. Yet it did not mark the St. Petersburg attack on Monday evening. It was only after facing criticism that Paris Mayor Anne Hidalgo announced Tuesday that the tower's lights would be dimmed in memory of the victims in Russia.

Tel Aviv City Hall was one of the few international monuments to pay tribute to the St. Petersburg victims, as it had the British victims, lighting up the building in the colors of the Russian flag.

The relative lack of international sympathy wasn't lost on observers. Russian state media outlets RT and Sputnik ran stories noting that neither the Eiffel Tower nor the Brandenburg Gate recognized the St. Petersburg victims on Monday. Social media users in Russia and elsewhere suggested a double standard in how the West responds to attacks.

Such an accusation is not new. Terrorist attacks in Western Europe or the United States generally receive widespread and almost immediate attention, but the far more frequent and generally far more deadly attacks in the Muslim world often pass by barely acknowledged. Islamic State suicide bombings in Baghdad don't prompt many people to change their Facebook profile picture to that of the Iraqi flag, for example, even when hundreds of civilians are killed.

For Russians, the problem is also compounded by their country's troubled international reputation. Even Trump, who has frequently expressed a desire for closer relations with Putin, may not have wished to associate himself with Russia at the moment, given the controversy surrounding his campaign's alleged links to the Kremlin. Russian belligerence in Ukraine and Syria also clearly affects the way many view attacks that target Russians.

Counterintuitively, Russia's long history of terrorism may make it even less sympathetic to outsiders. Over the past 20-plus years, Russia has suffered several deadly attacks. By one measure, it has suffered the most terrorist attacks of any European nation since 1970, but the Russian state has often responded harshly and clumsily to these incidents. Some would argue that these responses put more Russian citizens at risk.

One well-known conspiracy theory suggests that apartment bombings in 1999 that killed more than 300 people in Russia were actually the work of the state itself, designed to propel Putin into office and justify a new war with Chechen rebels. Some notable figures, including Garry Kasparov, a Russian pro-democracy activist and former world chess champion, hinted at state involvement in Monday's bombing but offered no corroborating evidence.

Distrust of the Russian state is understandable in today's climate, but the lack of international response and the spread of conspiracy theories in the wake of Monday's attack have perturbed even Kremlin critics. Mark Galeotti, a British-born expert on Russian security, wrote in the Moscow Times on Tuesday that the apparent international apathy only “played into the hands of a Kremlin narrative that has been deployed again and again on far flimsier grounds” — namely, that the West wants bad things to happen to Russian people.

The international response also ignores the fact that the victims of Monday's attack were ordinary Russians, living their life in a grand, creative and distinctly European city. And these St. Petersburg residents responded to the attack with compassion and solidarity, offering free lifts to commuters left stranded by the attack or queuing to donate blood to the victims.

It was the sort of reaction that would make people proud — whether they lived in Russia, Britain or anywhere else.

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