A Muslim Russian national from Kyrgyzstan detonated an explosive device in St. Petersburg's subway system in April, killing 14 people and injuring many others. The attack signaled a growing Islamist threat facing Russia, following several high profile terrorist attacks in recent years. More people have been killed in Russia from terrorism than any other European state since 1970. Yet Russia maintains a glaring double standard when it comes to terrorist violence and now sponsors some of the deadliest terrorist groups in history.

For the Russian government, terrorists aren't "terrorists" if they avoid targeting Russian citizens or interests. In this light, Russian officials consistently avoid classifying groups like Hamas and Hizballah as terrorist organizations. The latest example came directly from Russia's ambassador to Israel, Alexander Shein, in an interview last Friday with Israel's Russian-language Channel 9 and translated by the Middle East Media Research Institute (MEMRI).

Shein admitted that while both groups were "radical organizations, which sometimes adhere to extremist political views," Russian law only designates organizations as terrorists when they "intentionally conduct acts of terror in Russian territory, or against Russian interests abroad – installations, embassies, offices, or citizens."

Despite the lack of a universal definition, "terrorism" generally refers to a non-state actor's deliberate threat or use of violence for primarily political, religious, or ideological purposes. According to many conceptions, terrorism tends to intentionally target civilians, but also to create a broader psychological reaction beyond those killed or injured. By these well-established criteria, Hizballah and Hamas, organized militant groups that purposefully kill civilians to establish Islamist states in their image, are the quintessential terrorist organizations.

For the Russian government, a jihadist blowing up a St. Petersburg metro constitutes terrorism. But a Hamas suicide bomber targeting Israeli public transportation or Hizballah militants indiscriminately firing rockets into civilian areas is not terrorism. With such a view, it is no surprise that Russia is actively engaging in a double game when it comes to supporting terrorist organizations.

Since launching its 2015 military intervention in Syria's civil war, Russia has positioned itself as a major benefactor to the Iranian-led Shi'ite axis operating in Syria. Russia provides military training and air support to Hizballah fighters on the ground. Russia reportedly supplies the terrorist group with heavy weaponry and enables the flow of sophisticated armaments from Iran to its terrorist proxy.

Russia historically has faced diverse terrorist threats from its North Caucasus region, a conflict that has increasingly adopted a more global Islamist orientation. In December 2013, Islamist terrorists conducted two suicide bombings within two days, targeting public transportation in the city of Volgograd. Another suicide bombing had taken place in the same city two months earlier. Since the mid 1990's, Russian forces have fought North Caucasian militants in two bloody wars and other sustained battles in the region. Despite strong crackdowns in recent years, Russian security services allegedly encouraged many local extremists to leave the North Caucasus and join terrorist organizations in Syria, disregarding its own laws deterring individuals from fighting with terrorist groups that oppose Russian interests. Since 2011, an estimated 2,400 Russians have travelled to Syria to fight with various militant groups, including the Islamic State and al-Qaida's affiliate Jabhat al-Nusra. Now, Russia is particularly vulnerable to the threat from returning foreign fighters.

In Afghanistan, Russia has been increasingly supporting the Taliban under the pretext of combatting the Islamic State's affiliate in that country. Like Syria, Russia is allying with one terrorist organization to fight another one. In both contexts, these policies may be intended to reduce the domestic terrorist threat to Russia and enhance Russia's influence. But working with terrorist entities that hold long-standing grievances with the Russian state in order to fight other short-term terrorist threats, will likely backfire.

The Islamist terrorist threat to Russian national security is unlikely to wane anytime soon. Russia's population is in decline, but Muslims living in Russia maintain relatively high birthrates. Some projections suggest that Muslims – which currently represent about 16 percent of Russian citizens – will account for one fifth of the country's population by 2020. Support for various types of Islamist groups abroad does not bode well for long-term Russian counterterrorism efforts at home. Russia's marginalized and predominately Sunni Muslim population may become even more susceptible to radical Islamist ideologies as Russia continues to support Shi'ite terrorist organizations in Syria.

Russia's explicit military, financial, and diplomatic assistance to some of the most brutal powerful terrorist groups make it one of the world's leading state sponsors of terrorism today. All acts of Islamist terrorist violence needs to be condemned and supressed uniformly, not in Russia's selective way.