Moscow(CNN) It took a matter of hours on Thursday for Russian President Vladimir Putin to rupture Europe's peace and security in his attempt to strip Ukrainians of their right to self-determination.
With air, sea and ground attacks, the full-scale invasion of Ukraine continued into Friday, with US sources familiar with intelligence warning that the capital, Kyiv, could fall within days.
Putin has been very clear about his basic goals in invading: He wants to disarm Ukraine, sever its ties to the NATO military alliance and end the Ukrainian people's aspirations of joining the West.
"We will seek to demilitarize and denazify Ukraine," Putin said of the country, led by a Jewish president, Volodymyr Zelensky, in a speech broadcast minutes before strikes began on Thursday.
"As well as bring to trial those who perpetrated numerous bloody crimes against civilians, including against citizens of the Russian Federation," Putin said, repeating a baseless claim of genocide in areas of Ukraine's Donbas region controlled by Russian-backed separatists.
Those, in short, are Putin's aims. But guessing exactly how he plans to execute that plan is a different matter.
Kremlin spokesman Dmitry Peskov on Friday declined to answer repeated questions on the objectives of its invasion of Ukraine and when hostilities might end. But history can serve as a guide for understanding Putin's possible endgames.
Since Russia's annexation of Ukraine's Crimea in 2014, several possible scenarios have become apparent:
The Russian government has already recognized the breakaway statelets of the Donetsk and Luhansk People's Republics in eastern Ukraine.
This week, the Russian military has made a grab for much bigger pieces of territory, pressing an offensive around Kharkiv, the biggest city in eastern Ukraine, and in the south, around the city of Kherson.
If Russian forces are able to capture Ukraine's port city of Odessa, it's possible to imagine a land bridge extending all the way across southern Ukraine, potentially even linking Transnistria -- a separatist enclave in Moldova, where Russian troops are stationed -- to Odessa, Crimea and southern and eastern Ukraine.
Putin, in his tendentious history of Ukrainians and Russians as "one people," has noted that the western edge of modern-day Ukraine was incorporated into the Soviet Union by the late dictator Joseph Stalin.
Parts of this region previously belonged to interwar Poland, Czechoslovakia and Romania, and, before that, the Austro-Hungarian empire. If Putin has partition in mind, Galician Ukraine and the city of Lviv -- close to the Polish border -- could potentially be a part of a sort of rump Ukrainian state, while Russia focuses its attentions on the east of the country.
A division along these lines could make Ukraine "look like Germany in the Cold War era, with western Ukraine more dependent on Europe, and the Eastern part" sucked into the Russian spheres of influence, which include Belarus, Russian historian and author Alexander Etkind told CNN.
That kind of redrawing of borders may be an expansionist fantasy, but it could separate out what Moscow -- justifiably or not -- perceives as a more nationalist part of Ukraine.
"Putin would love for every politically active and independent minded (Ukrainian) to leave his part of Ukraine," Etkind added.
Carving up the country was hinted at by Putin in his Wednesday morning broadcast. "Let me remind you that the people living in territories which are part of today's Ukraine were not asked how they want to build their lives when the USSR was created or after World War II," he said, indicating a Crimea-style referendum.
"Freedom guides our policy, the freedom to choose independently our future and the future of our children. We believe that all the peoples living in today's Ukraine, anyone who want to do this, must be able to enjoy this right to make a free choice," Putin said.
Western intelligence officials warn that Russia is planning to topple Ukraine's democratically elected government, replacing it with a puppet regime.
Putin has suggested he sees the current democratically elected government in Ukraine as illegitimate, and lamented the ousting of pro-Russian President Viktor Yanukovych in 2014. Ukraine does have other politicians who might be eager to fill the ranks of a pro-Russian government, installed possibly by force.
One of Putin's top allies in Ukraine is Viktor Medvedchuk, a prominent politician and oligarch. He faces allegations of treason in Ukraine and has been under house arrest.
A somber Zelensky vowed to stay on in Kyiv on Thursday, saying Russian sabotage groups had already entered the capital and have marked him "as target number one, my family -- as target number two," he said in a video statement. "They want to destroy Ukraine politically by destroying the head of state."
Russia says it doesn't want to be an occupier, but it's easy to imagine a scenario where Russia tries to impose its form of heavy-handed rule on Ukraine.
That would be hard pill for Ukrainians to swallow: they live in a country with a free press, freewheeling local politics and a tradition of street protest. Many Ukrainians view the Russian political system -- where genuine opposition protests are largely banned, or very difficult to organize -- with great foreboding.
Putin has had no problem backing violent local strongmen with scant regard for human rights.
Russia's air force backed President Bashar al-Assad in the Syrian civil war, providing overwhelming firepower to crush the country's armed opposition groups and flattening entire neighborhoods in the process.
Putin's own political rise began with the pacification of Chechnya, a breakaway republic in Russia's north Caucasus.
Russia's campaign there culminated with the installation of Ramzan Kadyrov, a local warlord and former rebel who is accused of running the Caucasus republic like his personal fiefdom. Activists say LGBTQ people and political opponents are hounded and persecuted -- with some alleged to have been abducted, tortured or disappeared.
Russia has a fearsome domestic security apparatus that jails and persecutes dissidents and keeps potentially troublesome opponents out of politics.
Ukrainians living in Crimea -- which was occupied by Russia in 2014 and annexed after a referendum widely seen as a sham -- experienced first-hand what it's like to live in a state where the FSB, Russia's state security service, is all-powerful.
Filmaker Oleg Sentsov, one of Ukraine's most prominent former prisoners of conscience, was brought up on what have been described by rights groups as ludicrous charges, including terrorism, arms trafficking and organization of a terror group.
He was arrested in Crimea in 2014 after peacefully opposing the Russian occupation. He received a 20-year Russian prison sentence in 2015, but was released in a 2019 prisoner exchange with Ukraine and has since spoken extensively about his torture in the custody of Russian authorities.
Like Senstov, Ukraine now faces the strong arm of Russia for daring to oppose Putin's revanchist vision. The country's ability to choose its own future now rests on its fighters, who battle Russian forces alone.