It's not archived online, but in 1999 there was a Moscow Times article shortly after the Russian apartment bombings, where witnesses claimed seeing FSB men plant barrels in the basements of the buildings shortly before the explosions. Back then, nobody thought anyone would ever delete anything off the internet, so archive.org did not archive the story. You have only this Wikipedia link, its sources, https://en.wikipedia.org/wiki/1999_Russian_apartment_bombings and my memory to go on here. Maybe you can find the original citation, I can't. (This is the best I can do, but it's not the original Moscow Times Article)(https://www.wilsoncenter.org/publication/foiled-attack-or-failed-exercise-look-ryazan-1999) In any case, it was the Russian apartment building bombings of 1999 that triggered the Second Chechen War, where Putin said something like, “If we catch them in the shithouse, we'll kill them right there.” The bombings seemed convenient. After a disastrous First Chechen war that started the Western conversations about a disintegrating Russia (See any late 1990s editions of The Economist), Russia needed to change optics if it was going to get buy-in for a second war. Putin must have watched Pulp Fiction and been inspired.
A tough talking leader willing to annihilate a medium sized city in order to defeat an insurgency? (https://en.wikipedia.org/wiki/Battle_of_Grozny_(1999%E2%80%932000)) Quite a bit of symmetry there. Except this time, we're not talking about Grozny, we're talking about Ukraine. And instead of an apartment bombing, it's fireworks over the Kremlin.
It didn't even hit the building, just a flagpole. And it happened just before Victory Day. Good timing... but for who? Russia was already planning a major offensive this month. We know this from the financial flows, hardware production stats, and the conscription and retraining timetables for Russia.
Ukraine's attacks have a desperation more akin to bank robbers gone rogue, than a military operation. (https://en.wikipedia.org/wiki/2022%E2%80%932023_Western_Russia_attacks). While the attack on the Kremlin matches the chaotic style of Ukrainian partisans, it seems more fortuitous for Moscow than Kiev. The Military Summary Channel (“Hello my dear friends...”) theorized that with Zelensky in Finland, it's possible the attack was planned by the ruling Ukrainian elite, using NATO as a shield.
What advantage would Ukraine gain from this? To provoke an escalation from Russia so the West gives Ukraine more arms? Sounds nice, except the West can't do much more than it's already doing. Ukraine is expecting 1940s America to come to its rescue? We sold that off to China 20 years ago. Now we have low intensity kinetic warfare, and high intensity economic warfare.
There is evidence of at least one outsider clique in Russia that is not happy about the way the war has been conducted. We see hawkish comments in Russian Media, the Military Summary Channel, and the Ukraine war threads on Moon of Alabama (moonofalabama.org). They all want to know why Russia isn't blowing the crap out of Ukraine. Losers always want to take over when a winner has already done the job for them. They want to get rid of Shoigu, even though he's the guy who fixed their munition supply chains. Amateurs talk tactics, Generals talk logistics. Also, destroying your victory conditions isn't the same as achieving them. This shows a level of crudeness that has thus far not been on display by the Russian General Staff. But we've seen crudeness in the background. It seems quite likely that some faction tried killing Shoigu with curare or some heart attack weapon. Ever notice that in Russia, heart attacks only seem to afflict people with lots of enemies?
Russia is not monolithic and Putin is not omnipotent there. Shoigu is not white enough for many Slavs. Well, the outsider is always used to do the unpopular and then get used as the scapegoat.
He's outlived his usefulness in their opinion. It was fine when he was fixing all the supply chain problems and dealing with the entrenched procurement bureaucracy's corruption, but now that production is going, he's in their way. Maybe they want more bribes. Putin had to keep firing staff at the Vostochny Cosmodrome (https://en.wikipedia.org/wiki/Vostochny_Cosmodrome) when it was being built, because of the extreme theft. (https://www.themoscowtimes.com/2018/02/26/russias-vostochny-cosmodrome-bosses-jailed-mass-corruption-a60628) (https://www.bbc.com/news/world-europe-50462431) (https://www.rferl.org/a/russia-vostochny-cosmodrome-corruption/31558418.html) (https://www.theguardian.com/world/2019/nov/22/russia-launches-crackdown-on-spaceport-corruption-vostochny-cosmodrome) Maybe somebody thinks Shoigu is not hawkish enough and not letting them steal enough.
A little noticed story from five months back seemed to suggest that Russia was bracing itself for attacks on its territory. (https://www.thedailybeast.com/kremlin-official-andrei-gurulev-warns-of-more-ukrainian-strikes-on-russian-soil) What timing, since by that point, Russia had already conscripted its first wave of soldiers. If only they could psychologically justify the mass violence a major offensive necessarily entails... like a drone attack on the Kremlin. This could be the psychological operations template for the war: always portray Russia as the side with restraint, responding to an unacceptable escalation only after all other alternatives have been exhausted. A drone attack on the symbol of the Russian government is bound to antagonize and galvanize the public, or at least public taste-makers who will do their best to enforce conformity. A drone attack can be used to justify an escalation of combat intensity. This way, Russia isn't doing some Soviet style 'Victory Day Offensive,' Russia is merely 'replying' to a Ukrainian provocation. A drone bomb is used much the way a policy paper used to be used in Washington. A little Reichstag bombing cosplay to make the war more palatable.