His killing has once again shaken the world of Russian politics and has shown just how sick it is with hatred, mistrust and intolerance -- even toward a former senior Russian official. Many have expressed their condolences. Some of those sentiments were sincere -- even coming from his political opponents, while some were insincere -- even coming from his political "friends."
Many different theories concerning his murder have already been put forward, including an increasing number that point to the moral degeneracy of the people. It is difficult to shake the feeling that those who maligned Nemtsov while he was alive by, for example, publishing transcripts of his telephone conversations, continue that perverted abuse after his death.
Of course, there are also plausible theories for his murder. But somehow it seems that the "Nemtsov case" is one of those that will drag on for years without a definite resolution. And even if the actual perpetrators are caught and punished, I think the public will never learn all of the circumstances surrounding his murder -- at least not in the current political era.
Prior to this, the killing of Galina Starovoitova in November 1998 was the most high-profile political assassination in Russia. That case was finally solved last spring with the identification of the perpetrators and one of the individuals who ordered the killing.
However, the motives for the murder were never clarified: Investigators chose not to delve into the wilds of the complex relations between politicians and the St. Petersburg mafia. One line of inquiry that drew particular attention -- the theory that Vladimir Barsukov, the "dark lord" of St. Petersburg in the 1990s, was linked to the killing -- quickly fizzled out.
The authorities also claim to have apprehended and convicted the killers of former Novaya Gazeta journalist Anna Politkovskaya. And yet, the authorities have never bothered to explain why her alleged killers -- Chechens and a former member of the siloviki -- killed an opposition journalist.
That case carried political repercussions beyond Russia's borders, just like Nemtsov's murder, that some are already calling the second "Flight MH17" for the Kremlin -- a reference to the downing of a Malaysia Airlines passenger plane over separatist-controlled eastern Ukraine last July.
The two crimes share a cynical type of symbolism: Politkovskaya was murdered on President Vladimir Putin's birthday, while Nemtsov was murdered in what appears to be a special operation just a few dozen meters from the Kremlin, and on Putin's newly minted "Polite People Day" that honors Russia's Special Operations Forces.
The specific motives behind political murders are often less important than the impact those crimes have on the country's larger political processes. It is noteworthy that some observers are already comparing the murder of Nemtsov with the "Reichstag fire" or the murder of Sergei Kirov. The former marked the start of the Nazi terror in Germany while the latter served as a pretext for former Soviet leader Josef Stalin to unleash his political repression.
They note that the murder has already elicited a response from senior Western officials, including U.S. President Barack Obama, and that it is seen in the West not only as the murder of a politician, but also as the murder of one of Putin's most implacable opponents. Now their names are forever linked in this regard and the demonization of the Putin regime will only intensify in the West. It is even possible that the organizers were counting on that result.
Russia's right-wing political conservatives have already begun circulating the theory that the U.S. State Department and CIA instructed the Ukrainian Security Service to kill Nemtsov and provided the intelligence needed to carry it out. The alleged reason: Nemtsov had "failed to meet their expectations" in organizing an "Orange Revolution" in Russia or they had simply wanted to "strike a blow against Putin" and to use Nemtsov's death to spark a Maidan-style uprising all across Russia.
The same reactionary politicians and journalists have also put forward the no less cynical theory that Nemtsov was made a "sacred sacrifice" in order to revive and unify the moribund Russian opposition.
At the same time, Nemtsov's supporters claim that he was preparing to publish a report filled with facts and figures proving the Russian military's involvement in the Donbass. However, this version of events has exactly the same amount of supporting evidence as that put forward by the Russian ultra-patriots -- that is, none at all.
One particularly interesting theory concerns Nemtsov's anti-corruption activities. He might very well have made enemies during his term as an uncompromising politician in the Yaroslavl region. He not only gained a State Duma seat from that region, but was also squeaky clean in his conduct, a fact that rumor suggests led to several prominent figures there losing their jobs.
According to this theory, those disgruntled individuals might have staged his murder just outside the Kremlin walls to make it look like a high-profile political assassination -- theoretically a very effective diversionary tactic.
The same applies to still another theory. Immediately after the murder, an assistant to Nemtsov wrote on Twitter that the politician had been investigating corruption among medical professionals in the oncology field. If rumors are true that doctors blackmail terminally ill cancer patients into signing over the titles to their apartments in return for treatment, it would seem that such people would stop at nothing to prevent Nemtsov from revealing their crimes to a wholly unsuspecting public. However, there is no evidence to support that theory either.
The only thing that is definitely clear about the Nemtsov case is that it takes Russian society yet one more step along its very dangerous evolutionary path. That evolution began in connection with the war in Ukraine, and the war will continue to drive the process further.
Worse, this seems to be only the beginning of the journey, with a long way remaining before we hit bottom. It is difficult to imagine all of the political consequences this downward evolution will engender, but there is a growing sense that, whatever they are, they will be very dire, indeed.